MLB 2021 Opening Day Betting Preview - Back the Dodgers and Rays to Cover the Spread

SI Gambling analyst Roy Larking previews MLB Opening Day action and shares the two top picks on his Thursday baseball betting card.
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2021 MLB Opening Day Preview

Following a month of spring training games, the 2021 Major League Baseball regular season begins with all 30 teams in action today. After playing a 60-game schedule last year, which began in late July due to COVID-19 issues, the traditional 162-game schedule returns this season. The 91st MLB All-Star Game is scheduled for July 13, at Truist Park in Atlanta, and the regular season ends on Sunday, Oct. 3. After 16 teams advanced to the postseason last year, the standard 10-team playoff format is back in place this season. Here are my top two plays during the Opening Day action.

Bet on MLB action all season at DraftKings Sportsbook

Los Angeles Dodgers at Colorado Rockies

Los Angeles begins their 2020 World Series title defense with a three-game series on the road against Colorado. First pitch for the Dodgers vs. Rockies contest is scheduled for 4:10 p.m. ET at Coors Field in Denver, Colo. These teams met 10 times last season, and Los Angeles was the favorite in each of those games. The Dodgers went 7–3 straight up and 6–4 against the spread. UNDER bets had a slight advantage with a 5-4-1 record on run total wagers. Los Angeles went 3–1 SU and ATS, during four games played in Denver last season, and they outscored Colorado by a 33-16 margin.

Colorado opened with an 11–3 record last season, but went just 15–31 the rest of the way. They finished second last in the NL West standings with a 26–34 record. Pitching was a problem for the Rockies as they allowed a league-leading 353 runs and posted a 5.63 team earned run average. Colorado ranked 15th overall with 275 total runs scored. The Rockies went 12–18 at home last year and were outscored by a 213–153 margin in those games. In his 2021 Colorado fantasy baseball preview, SI fantasy expert Shawn Childs notes that a rebuilding process continues in Colorado.

Los Angeles opened the 2020 MLB season with an 11–7 record before winning 32 of their final 42 regular season games. They finished first in the National League West with a 43–17 record. The Dodgers led the league with 349 runs scored, and their 3.02 team ERA was first overall as well. Los Angeles went 13–5 in the playoffs, and defeated Tampa Bay (4–2) to claim their first World Series title since 1988. Acquiring pitcher Trevor Bauer, who won the 2020 NL Cy Young award, was a big off-season move by the Dodgers. It’s World Series or bust for the defending MLB champions.

German Marquez is making a second straight Opening Day start for Colorado. Marquez allowed two hits and one run, over 5.2 innings pitched, during the Rockies’ 1–0 loss on the road to the Texas Rangers on Opening Day last season. Clayton Kershaw is making a franchise record ninth Opening Day start for the Dodgers. During his first eight starts, from 2012 to 2018, Kershaw went 5–1 with two no-decisions. Los Angeles defeated Arizona 12-5 and San Francisco 10–4 during their last two season openers. Although the run line juice is expensive, bet on the Dodgers to win and cover the spread.

Pick: Los Angeles Dodgers -1.5 (-137) ATS at DraftKings

Betting Odds via DraftKings Sportsbook – Game Time 4:10 p.m. ET

Betting Odds via DraftKings Sportsbook – Game Time 4:10 p.m. ET

Tampa Bay Rays at Miami Marlins

Tampa Bay begins their 2020 American League title defense with a three-game series on the road against Miami. The first pitch for the Rays vs. Marlins matchup is slated for 4:10 p.m. ET at LoanDepot Park in Miami, Fla. This is one of three interleague games on the Opening Day slate. Tampa Bay went 5–1 straight up and 3–3 against the spread during six meetings last season. That includes a 3­–0 SU and ATS record as visitors. Nine or more runs were scored in four of the six contests. The Rays have won five straight games in Miami by a 23-7 combined count, and four of those victories were shutouts.


Miami performed above expectations last year as they finished second in the NL East Division with a 31–29 record. That was quite a turnaround after the Marlins went 57–105 during the 2019 MLB season. Miami made the playoffs for the first time since they upset the New York Yankees (4–2) and won the World Series in 2003. They defeated the Chicago Cubs (2–0) in the wild-card round before being swept 3­–0 by the Atlanta Braves in the NL Division series. The Marlins were outscored by a 304–263 margin last year, and a lack of offense is a concern heading into the 2021 season.

After beginning the 2020 MLB season with a 6–8 record, Tampa Bay won 34 of their final 46 games. They finished first in the American League East with a 40–20 record. The Rays outscored their opponents by a 289–229 margin during the regular season, and their bullpen led the league with 23 saves. For the first time since 2008, the Rays lost to the Dodgers (4–2) in the World Series after winning the AL championship. Starting pitchers are a concern for Tampa Bay after they traded Blake Snell to San Diego and Charlie Morton moved on as a free agent during the offseason.

After losing 6–4 to the Blue Jays last year and 5–1 to the Astros in 2019, Tampa Bay has lost two straight season-opening contests. Tyler Glasnow, who averaged 14.3 strikeouts per nine innings last season, makes his first Opening Day start for the Rays. Sandy Alcántara is making a second straight Opening Day start for Miami. Alcántara allowed three hits and one earned run, over 6.2 innings pitched, during a ­5–2 season-opening win against Philadelphia last year. That was the Marlins' first Opening Day victory since the 2014 season. Lay the run line and back Tampa Bay to win and cover.

Pick: Tampa Bay Rays -1.5 (+114) ATS at DraftKings

Betting Odds via DraftKings Sportsbook – Game Time 4:10 p.m. ET

Betting Odds via DraftKings Sportsbook – Game Time 4:10 p.m. ET


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