MLB Roster Expansions: What to expect from Lazaro Montes, Ethan Salas, more

On Tuesday, MLB rosters expanded for the final month of the regular season, which meant that every single organization was able to add two players to their active roster. While pretty much every team added a reliever to help their bullpens, and many of the other additions were bench players who can add depth at a variety of positions, there were some potential difference-making players who were added to the rosters.

Let’s see who they are and what we can expect from them over the final month of the season.

Lazaro Montes - OF, Mariners

Montes made quite the impression in his MLB debut on Tuesday, with a solo homer, an RBI single, and a walk as the Mariners beat the Red Sox. That was Montes’ first career MLB home run, but his 39th home run of the season. The 21-year-old has been swinging a hot bat over the summer, but has some contact concerns that I went over in more detail in a video this week.

Ethan Salas - C, Padres

Salas will make his MLB debut on Tuesday and will be the youngest player to enter an MLB game at catcher since Pudge Rodriguez did in October of 1990. This season, Salas hit .296/.374/.448 with 10 homers and 17 steals between Double- and Triple-A this year. That came with an impressive 5.4 percent swinging strike rate, and, in 24 games at Triple-A, he posted a 95 percent zone contact rate and 42 percent hard-hit rate. It’s incredibly impressive for a hitter at his age to control the strike zone and have the feel for contact that he does. MLB.com’s AJ Cassavell reports that, while there is no set role for Salas right now, he is “expected to catch, DH and serve as a bench bat.” That makes it sound like the left-handed-hitting Salas could start a few games a week with the chance to earn more playing time if he produces.

Leo Bernal - C, Cardinals

The 22-year-old is the seventh-ranked prospect in the Cardinals organization and hit .278/.363/.468 with 16 home runs, 77 RBI, and nine steals in 101 games at Triple-A this season. With Jimmy Crooks being sent down on Monday, Bernal could split time with Pedro Pages behind Ivan Herrera in St. Louis, but he started on Tuesday and hit sixth in the order. That was also against a left-handed starter, and Bernal is a switch-hitter while Pages bats right-handed, so that could be a signal that Bernal will be the true second option behind Herrera. Bernal had a 9.6% barrel rate and 40% hard-hit rate in Triple-A but posted a sub-average 75% zone contact rate, so we could have a few games like we did on Tuesday, where he went 1-for-5 with two RBI but also struck out twice.

Yohandy Morales - 1B/3B, Nationals

Morales is a player we have blurbed throughout the season because the 24-year-old former 40th overall pick in the 2023 MLB Draft had a tremendous year at Triple-A, hitting .286 with 25 HR and 76 RBI. If not for a mysterious injury that put him on the MiLB injured list in July, Morales could have been up earlier this season. This year, Morales pulled the ball more than he did in 2025 and got the ball off the ground more often. He still swings and misses a decent amount, but had a 13.2% barrel rate and 51% hard-hit rate at Triple-A this season. In his first two MLB games, he has played first base and designated hitter against two right-handed pitchers, which suggests that the Nationals are going to give him a chance to be a regular starter. Considering he went 3-for-5 with two runs scored, a double, and a solo home run against the Braves on Tuesday, that makes some sense, and he has enough power to be fantasy relevant down the stretch.

Adael Amador - 2B/SS - Rockies

Amador made his MLB debut at 21 years old back in 2024, but his first two chances at the big leagues did not go so well. He doesn’t chase outside of the zone, and he makes a lot of contact, but he didn’t hit the ball overly hard and struggled to adapt to the level. In 2026, he has been a similar player in Triple-A, but has hit the ball on the ground a bit less. Despite being primarily a shortstop, Amador has a solid glove and a strong arm, which means he can play all over the middle infield. The new Rockies regime might be more invested in Amador’s ability to make consistent contact and work a count. They had seemed to sour on Ezequiel Tovar a bit, so there’s a chance that Amador could push him for at-bats down the stretch.

Ricky Tiedemann - SP/RP, Blue Jays

You probably know who Tiedemann is because the 24-year-old was a top 100 prospect for a few years. The left-hander missed most of 2024 and all of 2025 while rehabbing from Tommy John surgery, and then experienced some elbow soreness again ramping up for camp in 2026, which has caused him to miss most of this season. His fastball is still sitting around 96-98 mph, and he’s throwing a new, harder, tighter slider, which should put less strain on his elbow after bone chips were also removed during surgery. He also has a strong changeup, and while Tiedemann will just be a reliever this season, finishing this year strong could give him the inside track to compete for a rotation spot in 2027.

Jedixson Paez - SP, Red Sox

The 22-year-old had allowed just four runs on seven hits in 12 1/3 innings while posting an 18/2 K/BB ratio in three starts for Triple-A Worcester before being called up on Tuesday. His first MLB start did not go so well. He allowed eight runs in 3 2/3 innings against the Mariners. He did throw 63 percent of his pitches for strikes, including 86 percent on his curve, and his changeup posted a 17 percent swinging strike rate against lefties, but his fastball locations were not good, and he simply doesn’t throw hard enough to get by without solid location. There’s a chance he gets another spot start this season to keep Boston’s regular starters fresh for the playoffs, and he could be solid rotation depth in 2027, but his impact this year remains unlikely.