MLB rosters expanded Tuesday, and with the calendar turning to the final month of the regular season, every team got two extra spots to work with. Most clubs used one of those openings on bullpen help, while plenty of the rest went to depth pieces who can bounce around the diamond. But a few teams brought up players who could actually change the look of their roster over the next month.
Lazaro Montes wasted no time making his presence felt for the Mariners. In his MLB debut Tuesday against the Red Sox, the 21-year-old launched a solo homer, added an RBI single and drew a walk as Seattle won.
It was Montes’ first career MLB home run, but hardly the first time he’s shown pop this season - the blast was his 39th homer of the year. He’s been locked in over the summer, though the contact questions that have followed him are still part of the picture.
The Padres are giving Ethan Salas his first shot in the majors on Tuesday, and the history attached to that moment is hard to miss. He becomes the youngest player to appear in an MLB game at catcher since Pudge Rodriguez in October of 1990.
Salas put together a strong season between Double- and Triple-A, hitting .296/.374/.448 with 10 homers and 17 steals. The underlying numbers were just as eye-catching: a 5.4 percent swinging strike rate, plus a 95 percent zone contact rate and 42 percent hard-hit rate in 24 Triple-A games.
MLB.com’s AJ Cassavell reported that there is no fixed role for Salas yet, but he is “expected to catch, DH and serve as a bench bat.” That setup suggests the left-handed hitter could get a few starts a week and force his way into more playing time if he hits.
St. Louis called up Leo Bernal, and the Cardinals’ seventh-ranked prospect arrives with a strong Triple-A line behind him: .278/.363/.468 with 16 home runs, 77 RBI and nine steals in 101 games.
With Jimmy Crooks sent down Monday, Bernal could share time with Pedro Pages behind Ivan Herrera, though Bernal started Tuesday and batted sixth. The fact that it came against a left-handed starter matters, since Bernal is a switch-hitter and Pages bats right-handed.
That could be a hint that Bernal is the real No. 2 option behind Herrera. He showed real damage ability in Triple-A with a 9.6% barrel rate and 40% hard-hit rate, but the contact still comes and goes; he posted a sub-average 75% zone contact rate and went 1-for-5 with two RBI and two strikeouts on Tuesday.
The Nationals are taking a look at Yohandy Morales, and there’s a good reason his name kept popping up all season. The 24-year-old former 40th overall pick in the 2023 MLB Draft crushed Triple-A pitching, hitting .286 with 25 homers and 76 RBI.
A mysterious injury that sent him to the MiLB injured list in July delayed his arrival, but the production was hard to ignore. Morales pulled the ball more than he did in 2025 and got the ball off the ground more often, though he still swings and misses plenty.
Even so, his 13.2% barrel rate and 51% hard-hit rate stood out. In his first two MLB games, he has played first base and designated hitter against two right-handed pitchers, which points to a chance to carve out a regular role.
He backed that up Tuesday against the Braves by going 3-for-5 with two runs scored, a double and a solo homer.
Adael Amador is back in the big leagues for the Rockies, and this time the path forward may be a little different. The 21-year-old got his first taste of MLB action in 2024, but those early chances did not go well.
His game has stayed pretty consistent: he doesn’t chase much and he makes a lot of contact, but he hasn’t always driven the ball with enough authority. In Triple-A this year, he’s been similar, though he has kept more balls on the ground than before.
A natural shortstop with a solid glove and strong arm, Amador can handle the middle infield anywhere. And with the new Rockies regime seemingly less committed to Ezequiel Tovar, there’s at least a chance Amador can push for at-bats down the stretch.
Toronto is also easing Ricky Tiedemann back into the picture. The 24-year-old lefty has carried top-100 prospect status for years, but injuries have slowed him badly.
He missed most of 2024 and all of 2025 while rehabbing Tommy John surgery, then dealt with elbow soreness again while getting ready for camp in 2026, which cost him most of this season too. The stuff is still there, though.
His fastball is sitting around 96-98 mph, and he’s now working with a new, harder, tighter slider that should put less strain on his elbow after bone chips were also removed during surgery. He also has a strong changeup.
For now, Tiedemann will work as a reliever, but a strong finish could set him up to compete for a rotation spot in 2027.
Boston’s Jedixson Paez came up after a strong run at Triple-A Worcester, where he allowed just four runs on seven hits in 12 1/3 innings with an 18/2 K/BB ratio across three starts. His first big-league start, however, was rough.
Against the Mariners on Tuesday, he gave up eight runs in 3 2/3 innings. There were a few encouraging details - he threw 63 percent of his pitches for strikes, 86 percent of his curves went for strikes, and his changeup generated a 17 percent swinging strike rate against lefties - but his fastball command was not good enough, and he doesn’t bring enough velocity to survive without sharper location.
He could still get another spot start later this season to help keep Boston’s regular starters fresh for the playoffs, and he may wind up as rotation depth in 2027, but his impact in 2026 looks limited.
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The twist has come elsewhere, with Alex Hoppe turning into a real weapon for the Orioles out of the bullpen and showing better pitching indicators than he had before the swap. Luis Castillo has also had a rough go of it with the White Sox, which only sharpens the sense that Seattles gamble is looking shakier by the week, even if the final judgment on the deadline still has some time to play out. [Read more 🡒]
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Since then, though, the confidence around Castillo has faded fast. His recent starts have featured more damage, with opponents piling on runs and leaving the yard, and that has only sharpened the concern in Chicago about a rotation that has already been under pressure. For Mariners fans watching from afar, it is a familiar kind of tension around a pitcher who can still flash quality, but whose current form leaves plenty of questions about what he would look like in a playoff game. [Read more 🡒]
Mariners Suddenly Have A New AL West Threat To Worry About
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For Seattle, the timing matters. The Mariners have been trying to hold their place in a division that can shift quickly, and a more aggressive, better-resourced Angels operation could change the balance over time. Los Angeles still has plenty to prove after years of disappointment, but if Kroenke treats the roster and the organization like a project worth pushing forward, the Mariners may have one more serious contender to keep an eye on. [Read more 🡒]