Week 16 MLB Prospect Watch: Samuel Basallo, Vaughn Grissom Lead Rising Infielders

Week 16’s MLB Prospect Watch zeroes in on infielders pushing for big-league promotions, from power-hitting catchers to toolsy shortstops. With several top prospects lighting it up in AAA—including Francisco Alvarez, Samuel Basallo, and Vaughn Grissom—it’s only a matter of time before these names make fantasy noise at the next level.

Catchers

Francisco Alvarez, New York Mets

The Alvarez banishment to AAA stands at 16 days. Over his 13 games, he hit .217 with seven runs, four home runs, nine RBIs, while striking out 16 times across 46 at-bats. Alvarez doesn’t have a hit over his previous seven at-bats, heading into Friday.

Over this span, Luis Torrens has a solo home run with no other production for the Mets over his 36 at-bats (.139), with a high strikeout rate (30.8%). New York’s backup catcher (Hayden Senger) is 3-for-16 (.188) over this span with two runs. The Mets' pitching staff allowed six runs or more in nine of 15 games since Alvarez was sent to AAA.

Samuel Basallo, Baltimore Orioles

Despite the Orioles losing Adley Rutschman and Gary Sanchez to injuries, Basallo sits and waits for his invitation to the big dance in the minors. At age 20, he already has half a season of experience at AAA (.253/49/20/52 over 277 at-bats). This year, his approach (38 walks and 52 strikeouts) improved over his 240 plate appearances.

Basallo hit .265 over his first 196 at-bats this season at AAA, with 38 runs, 17 home runs, and 42 RBIs, which translates to an impact power bat at the catcher position. Baltimore has played him at catcher (22), first base (15), and DH (19) this season.

First Basemen

Jonathon Long, Chicago Cubs

Over his last 10 games at AAA, Long went 14-for-43 with seven runs, four home runs, and nine RBIs. He’s now batting .317 on the year over 315 at-bats with 52 runs, 13 home runs, 57 RBIs, and two stolen bases. Long also handled himself well over the back half of 2024 (.340/42/7/29 over 159 at-bats) at AA with a stronger approach (35 walks and 33 strikeouts). His strikeout rate sits at 19.8% in 2025.

Brennan Milone, Athletics

In 2024 and 2025, the A’s gave Milone 644 at-bats at AA, leading to a .276 batting average with 105 runs, 25 home runs, 105 RBIs, and 12 steals. They promoted him to AAA in late May. His batting average (.241 over 83 at-bats) is trailing at the next level, but he continues to take walks (18) with a league average strikeout rate (21.9%). Milone only has two home runs and 13 RBIs so far at AAA, but he’s scored 19 runs.

Second Basemen

Vaughn Grissom, Boston Red Sox

Grissom wondered his way through his first season with the Red Sox after being acquired in the Chris Sale trade. His bat has been in form over his last 12 games at AAA (20-for-44 with 11 runs, two home runs, and 10 RBIs). On the year, Grissom is hitting .287 over 303 at-bats with 57 runs, eight home runs, 36 RBIs, and eight stolen bases. Boston could trade him in part of a deal later this month for another starting pitcher.

Max Anderson, Detroit Tigers

Over his last 49 games at AA, Anderson hit .337 over 202 at-bats with 31 runs, six home runs, 32 RBIs, and two stolen bases. His high level of success has yet to lead to a promotion to AAA. For the year, he has outperformed expectations (.333/47/11/53/2 over 291 at-bats).

Third Basemen

Warming Bernadel, Colorado Rockies

The direction of Bernadel’s bat has been up since the middle of May. Over his last 36 games, he went 51-for-135 (.378) with 26 runs, three home runs, 18 RBIs, and two stolen bases. Other than 302 at-bats at AA in 2023 (.225/30/6/28/2), he has hit over .300 for most of his minor league career. The development of his power will be the key to his long-term viability in the majors.

Murphy Stehly, Washington Nationals

After a promotion to AA in mid-May, Stehly has been on a productive pace in batting average (.328), runs (26), home runs (5), and RBIs (18) over his 119 at-bats. His bat showed growth in his final season at Texas (.367/65/19/61/8 over 278 at-bats), resulting in the Nationals drafting him in the 10th round in 2022.

Shortstops

Jeremiah Jackson, Baltimore Orioles

From 2022 to 2025, Jackson’s minor league home was AA, where his bat offered a dull batting average (.229) over 1,376 at-bats. He scored 172 runs, hit 59 home runs, and drove in 204 base runners while stealing 47 bags.

The Orioles promoted him to AAA in early June, and Jackson kicked up his game a notch (.372/19/8/15/5 over 121 at-bats) while striking out only 12 times. He’s riding a 12-game hitting streak (21-for-55 with seven runs, two home runs, four RBIs, and two steals).

JJ Wetherholt, St. Louis Cardinals

The Cardinals drafted Wetherholt seventh overall in the 2024 MLB June Amateur Draft. His bat offered the most value in 2023 at West Virginia (.449/67/16/60/36 over 225 at-bats). He finished his college career with the same number of walks (82) and strikeouts (82).

St. Louis gave Wetherholt 62 games of experience this year at AA (.300 over 223 at-bats with 39 runs, seven home runs, 34 RBIs, and 14 stolen bases). They promoted him to AAA earlier this week, leading to four hits over 11 at-bats with four runs, a home run, and two RBIs.