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2020 Fantasy Baseball: Seattle Mariners Team Preview

Full fantasy baseball stat projections for Mariners hitters and pitchers. What to expect from Mitch Haniger, Marco Gonzales and more.

Seattle Mariners

For the first two weeks of 2019, fans of the Mariners and fantasy owners with Mariners on his or her squad had loads of fun. They went 13-2 while scoring 117 runs (7.8 runs per game). It only took them three and a half weeks to suck the air out of their fast start. A pair of six-game losing streaks led to a 5-15 record. By the end of May, Seattle was already 10 games under .500. In the end, the Mariners missed the postseason for the 19th consecutive year. In the team’s 43-year history, they’ve made the playoffs just four times with no World Series appearances.

The demise of the team from 2018 (89-73) to 2019 (68-94) came from a massive step back in pitching. Seattle allowed 182 more runs than the previous season (711), leading to a 23rd-place finish in ERA (4.99). Their pitchers allowed 260 home runs (fourth most in baseball) while picking up 34 saves.

The Mariners did score 81 more runs than they did in 2018 (677), which moved them to 20th in the majors. They finished 12th in home runs (239) and 18th in RBI (730).

This season, their starting lineup will have the same cast of characters. Seattle projects to have nine hitters on their opening day roster that came via a trade. The two additions to the pitching staff from free agency are SP Kendall Graveman and RP Carl Edwards.

Over the long haul of a 162-game season, the Mariners don’t have the pieces to compete in any area of the game. They need to rebuild their starting rotation, and their bullpen is in transition, lacking a truly dominant closer. Seattle has some major league pieces to their offense, plus a couple of prospects that may help in 2020. The combination of the two still ranks below the league average. In essence, the Mariners lack a pair of aces, a stopper, and their first offensive player drafted in fantasy land comes off the board as the 152nd pick (Mallex Smith). For the record, Las Vegas set the Over/Under in wins for Seattle at about 66.5.

Starting Lineup


1. OF Mallex Smith

Smith played his way off of shallow fantasy rosters after the Mariners shipped him back to the minors in early May. His season started with only 16 hits over his first 97 at-bats (.165) with one home run, five RBI, and eight steals. It took him 10 games at AAA (15-for-48 with one HR, six RBI, and seven SBs) to punch his ticket back to the big leagues. 

He played much better over three months from June through August (.263 with 42 runs, four HRs, 24 RBI, and 25 SBs over 308 at-bats), but his at-bats regressed with each month played (June – 124, July – 95, August – 89, and September – 61). His season ended with more time on the bench due to a poor September (8-for-61 with no HRs, two RBI, and seven SBs). His strikeout rate (24.9) was a career-high while being well below his progress in 2018 (18.0). Smith also had regression in his walk rate (7.4). He did hold his own against lefties (.264), but right-handed pitching was a huge problem (.213 with 104 Ks over 362 at-bats). 

Smith led the American League in steals (46) with a slight bump in his AVH (1.474). He continues to have a ground ball swing (51.0) while ranking 16th in soft-hit rate (19.8). His skill set is unique, he provides an edge in speed, and his price point (ADP – 152) is reasonable. There’s a better player here, but he does have risk in three categories if he doesn’t clean up his approach. As bad as he played last year, Smith finished 62nd in SIscore (1.37) with a rating of +7.97 in the stolen base category. I’ll set his floor at .270 with 80-plus runs, five home runs, 50 RBI, and 50 steals.


2. SS J.P. Crawford

In his first chance at a full-time starting job in the majors, Crawford failed to live up to expectations. He did not make the Mariners out of Spring Training, which led to 31 games at AAA (.319 with three HRs and 15 RBI over 116 at-bats). After 17 games in the majors (.279 with one HR and six RBI over 61 at-bats), Crawford landed on the IL with a left ankle injury. He played well in June (.338 with two HRs and 17 RBI over 65 at-bats) while coming up empty after the All-Star break (.188 with three HRs, 21 RBI, and four SBs over 197 at-bats). 

Crawford was a disaster against left-handed pitching (.160 with no HRs and 10 RBI over 106 at-bats). His approach (strikeout rate – 21.0 and walk rate – 10.9) gives him a chance at hitting near the top of the batting order. Over seven seasons in the minors, he hit .269 with 46 home runs, 249 RBI, and 71 stolen bases over 2,261 at-bats. His CTBA (.298) remains low with no excitement on his recent resume. Possible double-digit home runs and steals with a full season of at-bats, but his batting average is going to be a negative until he makes harder contact (24.8 percent).


3. OF Mitch Haniger

Update: Haniger had his second back surgery in mid-February. His timetable to return to the field is unknown in early June.  

Haniger looked to be on his way to a great season after his start over the first 25 games (.274 with 26 runs, seven HRs, 18 RBI, and two SBs over 106 at-bats). Over his next 38 games, he hit eight home runs with 20 runs and 14 RBI, but his batting average (.179) turned into a massive liability due to a much higher strikeout rate (29.9). Haniger didn’t play a game after June 6th due to a ruptured testicle that required a second surgery in late January. Seattle expects him to miss some time in Spring Training while having a chance to play on Opening Day. 

In 2018, he improved his approach (strikeout rate – 21.7 and walk rate – 10.3), with both numbers being career bests. His CTBA (.379 – .327 in 2019) came in strong while falling in a tight range over his previous four seasons. Haniger improved his RBI rate (17) while offering strength in his average hit rate (1.729 – 2.111 in 2019). This season, he can be had in drafts with about the 198th pick with a low of 140 and a high of 244. In 2018, Haniger ranked 22nd in SIscore (4.17). A rebound should be expected (.270 with 80 runs, 25 home runs. 80 RBI, and 10 steals).


4. 3B Kyle Seager

Seager had left-hand surgery in mid-March to repair a tendon issue, which cost him the first eight weeks of the 2019 season. He struggled to find his way from May 25th to July 21st (.186 with six HRs and 18 RBI over 172 at-bats). His bat took over his next 25 games, which led to a hit in every game except one (.359 with 11 HRs and 24 RBI over 92 at-bats). Seager drove the bus home with six home runs and 21 RBI over his final 129 at-bats, but he only hit .225. 

His approach (strikeout rate – 19.9 and walk rate – 9.9) moved in a favorable direction. He continues to have a low CTBA (.306) while setting a career-high in his AVH (1.957). Surprisingly, Seager was a much better hitter against left-handed pitching (.285 with 11 HRs and 25 RBI over 130 at-bats) than righties (.217 with 12 HRs and 38 RBI over 263 at-bats). His hard-hit rate (39.7) came in at 168th, and he raised his HR/FB rate (17.0) to the highest level of his career. 

Seager continues to have a fly ball swing (43.8 percent). He has 20 or more home runs in each of his eight seasons, but his batting average has been a liability in each of his past three seasons (.249, .221, and .239). Not a bad backend swing at third base based on his ADP (379), as he should hit in the middle of the Mariners’ batting order with an 80/25/80 skill set.


5. 1B Evan White

Despite only having 18 career at-bats at AAA, the Mariners signed White to a $24 million contract in November for six seasons. Last year he hit .293 over 365 at-bats at AA with 18 home runs and 55 RBI while missing some development time due to a hip injury in April. His bat shined in June (.371 with eight HRs and 19 RBI over 97 at-bats). Seattle drafted him with the 17th pick in the 2017 MLB June Amateur Draft after he played well over three seasons in college (.356 with 17 HRs, 109 RBI, and 18 SBs over 655 at-bats). 

Over two-plus seasons in the minors, White hit .296 with 32 home runs, 133 RBI, and seven stolen bases over 906 at-bats. His strikeout rate (20.4) and walk rate (8.6) should be favorable in the majors. Although his CTBA (.392) grades well, his swing path may produce a high number of ground balls early in his career. White did have a high HR/FB rate (19.4) at AA. 

I’m getting a John Olerud feel here. White has a great glove with more underlying power. Based on his new contract and no one blocking him at first base, he should be in the big leagues early in 2020 if he doesn’t make the team out of Spring Training. A reasonable chance at a .280/20/80 player out of the gate while his power may be better than expected in year one of his pro career. 

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READ MORE: 2020 Seattle Mariners Team Outlook

Pitching Staff


SP1 Marco Gonzales

Gonzales threw the ball well over his first 10 starts (3.18 ERA and 42 Ks over 56.2 innings) despite showing some risk in his WHIP (1.296). He crushed fantasy teams over a four-game stretch from May 17th to June 2nd (9.58 ERA, 1.839 WHIP, and four HRs over 20.2 innings). Gonzales rebounded over his final 20 starts (11-7 with a 3.44 ERA and 93 Ks over 125.2 innings) while allowing two runs or fewer in 13 games. 

His walk rate (2.5) regressed from his 2018 success (1.7) while losing any strikeout ability (6.5 per nine). He struggled with lefties (.302 with eight HRs over 205 at-bats). His AFB (89.3) was a career-low. Batters had the toughest time with his changeup (.244 BAA). He had a serviceable cutter (.255 BAA) and four-seamer (.245 BAA). Strike thrower with no edge in velocity that can be had with the 426th pick this draft season. The risk outweighs the reward, which puts him in the avoid column for me in 2020.


SP2 Justus Sheffield

After appearing to be close to the majors after pitching well at AA and AAA in 2018 (2.48 ERA and 123 Ks over 116 innings), Sheffield was a bust for any fantasy owner thinking he would help in 2019. His season began with four reasonable starts at AAA (3.93), but he walked 14 batters over 18.1 innings. Seattle gave him one start in late April (two runs, seven baserunners, and four walks over three innings), before shipping him back to AAA. He pitched so poorly in nine starts (8.35 ERA and 1.991 WHIP), the Mariners had to drop him in class to AA. 

Sheffield regained his form over 10 starts (1.49 ERA, 0.9949 WHIP, and .218 BAA over 66.1 innings with 71 Ks). He struggled over his next four games between AA and the majors (7.20 ERA and six HRs over 20 innings), but Sheffield did get a taste of success in two games with Seattle (one run over 11 innings with 11 Ks) before running off the tracks again over his final three starts with the Mariners (11 runs and 23 baserunners over 13.2 innings with 15 Ks). 

His AFB (93.1) was league average while working off three pitches (four-seam – .284 BAA, slider – .302 BAA, and changeup – .320 BAA). Over six seasons in the minors, he went 43-33 with a 3.31 ERA and 640 strikeouts over 620.2 innings. This year I’d like to see more life on his fastball, and growth in his command (3.5 walks per nine in his minor league career). Worth a flier and follow based on his ADP (387). Possible help in strikeouts with plenty of WHIP risk earlier in his career. 


The Mariners signed Walker to a minor league contract in mid-February. His velocity was back in spring training, pointing to him making the major league team when the season starts. He pitched only four games in 2018 and 2019 (3.21 ERA and ten Ks over 14 innings) due to TJ surgery in April of 2018. Last season his progress was slowed by a right shoulder strain. In his only appearance at any level in 2019, Walker tossed one shutout inning with one strikeout.

Here is a look at his outlook heading into the 2018 season:

Walker showed growth in 2017, but a high walk rate (3.5) led to less progress. He set a career-high in his strikeout rate (8.4) while being tougher to hit (.247 BAA). Walker allowed 11 of his 16 home runs to righties with some failure against them in batting average against (.262). He had an ERA under 3.94 in each month while struggling with HRs in July (five over 29.2 innings) and August (five over 27.2 innings) then walks in September (18 walks in 30.2 innings). His AFB (94.0) was a career-low. Batters struggled to hit his four-seam fastball (.245 BAA), slider (.237 BAA), and curveball (.194 BAA). Walker still needs to find his rhythm with his split-finger fastball (.333 BAA) that was much more effective in 2016 (.229 BAA). He missed almost four weeks from May 19th to June 14th with a blister issue on his pitching hand. On the year, he allowed two runs or fewer in 15 of his 28 starts plus one disaster outing with five runs allowed or more. On the verge of becoming a frontline starter, which will come with better command. Walker has plus secondary pitches with a chance to improve strikeout ability. Value arm with his next step being a sub 3.00 ERA with 200-plus strikeouts.

In 2020, he’ll only be a flier with his draft value rising once Walker finds a new home.


CL/RP Carl Edwards

Over his five years in the majors, batters only hit .157 against Edwards. His high walk rate (5.1) over his career has been a massive problem for someone pitching in the 9th inning, despite his edge in strikeout rate (12.1). After pitching well in 2017 and 2018 (8-6 with a 2.81 ERA and 161 Ks over 118.1 innings), he turned in a lost year in 2019 (8.47 ERA and 19 Ks over 17 innings). 

His season started with a change in his motion to remove a hitch in his move to the plate off the mound. Edwards began the year at AAA (3.07 ERA and 14 Ks over 14.2 innings) before going on the IL with a hand issue. He battled a back issue in late June, and his season ended in mid-August with a right shoulder injury. His AVB (94.3) faded for the third straight season while still offering a plus slider. Edwards is tough to hit with strikeout ability, but his arm is loaded with question marks in 2020. Seattle doesn’t have a lot of talent in their bullpen, which gives Edwards a dark horse chance at saves if he’s healthy and throwing strikes.

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Use coupon code EDGE25 to receive 25% off your monthly season-long subscription. Shawn Childs is a 5-time high-stakes fantasy baseball national champ. Gain a cash-winning edge with FullTime Fantasy.

READ MORE: 2020 Seattle Mariners Team Outlook

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