Recent MLB Transactions and Fantasy Baseball Impacts: Several Re-signings, Padres Add Trio and More

A new week has arrived, and we'll start it by going over some MLB transactions that have happened the past couple days. 

We have signings and one trade to discuss, so let's dive right in!

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Padres Add Castellanos, Canning and Marquez

San Diego has been busy over the past couple days, adding Nick Castellanos, Griffin Canning and German Marquez. They all signed one-year deals.

Castellanos is expected to play at first base, in the outfield and at designated hitter for San Diego, but is only projected to be in a platoon right now. Being a righty, that means he might not be in line for a ton of playing time, but good results could change that.

The nearly 34-year-old is entering his 14th MLB season. He spent seven years with Detroit, four with Philadelphia, two with Cincinnati and a half-season with the Chicago Cubs.

Castellanos has a career .272 average and .321 on-base percentage. He had a .250 average and .294 OBP over 147 games last season.

Castellanos also had 72 RBIs and runs scored over 147 games last season. He had 137 total hits, including 27 doubles, 17 home runs and two triples, while also having four stolen bases, 32 walks and 133 strikeouts over 589 plate appearances.

He's primarily been an outfielder in his career, but has played a bit of third base. Manny Machado is the third baseman, so that isn't an option. Gavin Sheets is the first baseman, but is a better platoon guy, so that's where Castellanos is expected to factor in. 

Fernando Tatis Jr. and Jackson Merrill are two locked-in starting outfielders, with Ramon Laureano being the other. There's not a lot of playing time available for Castellanos at those outfield spots, unless there's injuries.

Miguel Andujar is the projected designated hitter, so that's the spot Castellanos could slide into the lineup more often, especially if he's hitting well.

Right now, Castellanos is just a deep-league fantasy asset, but good results could eventually move him into standard leagues, so keep tabs on him. He's been a fantasy asset in the past, and could definitely get back to that level while hitting in this loaded Padres' lineup.

Canning and Marquez are both starting rotation options. Canning is working his way back from an Achilles tear, but is expected to return in April or May of this season. Marquez is the projected No. 5 starting pitcher at this moment.

Canning has a career 4.65 earned run average over six years and 581 1/3 career innings. He has 553 strikeouts along the way. Canning went 7-3 with a 3.77 ERA over 16 starts for the Mets last season - he struck out 70 batters over 76 1/3 innings.

Marquez has spent his entire 10-year MLB career in Colorado, where he posted a 4.67 ERA over 1,146 1/3 innings. He had 1,069 strikeouts along the way.

He's an inning-eater and can hold down a rotation spot as others heal up or prospects are ready to go. Marquez could be bumped to the bullpen eventually, but as long as he's in the rotation, he's got some fantasy upside, so keep tabs on him. He's just worth drafting in deeper fantasy leagues, in my opinion.

Canning will be a fantasy option when he's back from injury, but I'd also look at him as just a deep-league fantasy option as well. Anyone who pitches for the Padres has decent fantasy upside and could be worth streaming in good matchups.

Gallen Back to D-Backs

Arizona brought back Zac Gallen on a one-year deal worth $22,025 million.

He's projected to be the team's No. 2 starting pitcher, only after Merrill Kelly. Ryne Nelson, Eduardo Rodriguez, Brandon Pfaadt and Michael Soroka are the other projected starters in a six-man rotation. If Arizona ends up using a five-man rotation, Gallen won't be in any danger of losing his spot.

The 30-year-old righty has been in Arizona for most of his seven-year career. He has a career 3.58 ERA, but had an ugly 4.83 mark last season.

Across 33 starts in 2025, Gallen went 13-15. He struck out 175 batters over 192 innings, so at least he was able to eat some innings.

He's a bounceback candidate in 2026, and is on the average draft position list around pick 150. I'd expect that to go up a bit after he found a home.

As long as that ADP doesn't go too high, I think Gallen is worth a late-round pick. That makes him a very good option in deeper leagues, and worthy of rostering in some standard leagues as well.

Brewers Add Infielder

Milwaukee signed Luis Rengifo to a one-year deal worth $3.5 million.

He spent the first seven years of his career with the Angels. He has a career .250 average and .307 OBP. In 78 games in 2024, Rengifo had a .300 average and .347 OBP, but he regressed to a .238 average and .287 OBP over 147 games last year.

Milwaukee seems like the perfect home for Rengifo, and he's projected to be the starting third baseman, so he has fantasy value right away. There's other infielders who could play third, so Rengifo will have to hit to stick in the lineup.

Rengifo isn't on the ADP list right now, but I could see him getting some deep-league attention. He has standard league upside, so he's worth watching in case he takes off with the Brewers.

His fantasy outlook is higher because he's got a better team/lineup around him. Don't forget about Rengifo as the 2026 season gets rolling.

Hernandez Back in LA

Enrique Hernandez is back with the Dodgers on a one-year deal worth $4.5 million.

He's coming off left elbow surgery, and is expected back in May. Hernandez has played every single MLB position but catcher over his 12-year career, so he could help out all over the place when he's back.

Hernandez is more of a depth option, but in that loaded lineup, regular playing time could turn anyone into a good fantasy asset. That makes Hernandez a player to keep tabs on, even if he's just a depth option.

He has a career .236 average and .305 OBP. He has a little pop, but maybe most importantly is eligible to play at several spots. Hernandez is not a huge fantasy asset, but he's worth tracking just in case he ever gets in a groove.

Sewald Returns to Arizona

Paul Sewald re-signed with Arizona for one year, worth $1.5 million.

Over his nine-year MLB career, Sewald spent parts of two seasons with the D-Backs. He was with them in 2023 and 2024.

He posted a 4.31 ERA in his last year in Arizona, then posted a 4.58 ERA between stops in Cleveland and Detroit in 2025. Sewald has a career 4.11 ERA, so he's capable of much better results.

He's closed games in the past, and is projected to be the co-closer in Arizona with Kevin Ginkel. If Sewald is getting save chances, then he's got some fantasy upside.

Justin Martinez and A.J. Puk are closer options who are already on the 60-day injured list because of Tommy John surgeries in June of last year. Andrew Saalfrank is another reliever on the 60-day IL already.

Along with Ginkel, Ryan Thompson is another late-inning relief option. All-in-all, Sewald has a pretty decent shot at saves, if the Arizona bullpen doesn't add any more relievers.

The closer situation in Arizona will be worth watching in spring training. If anyone emerges as the go-to closer, their fantasy stock will shoot way up. Right now, Sewald and Ginkel are the best fantasy relievers in Arizona, but they are just worth holding in deeper leagues.

We'll see if anyone emerges and can become a standard league asset.

Astros, Blue Jays Swap Outfielders

Houston and Toronto swapped outfielders, with Joey Loperfido going to Houston and Jesus Sanchez heading to Toronto.

Sanchez is expected to be in a platoon, but being a left-handed hitter, he could play enough to have some fantasy relevance. He will help out as Anthony Santander is out several months with a shoulder injury.

Sanchez is a 28-year-old who has spent time with the Marlins and Astros over his six-year career. He owns a career .239 average and .307 OBP, but only had a .237 average and .304 OBP over 134 games in 2025.

He should get enough playing time in 2026 to have some fantasy upside. I'd look to him as just a deep-league option for now, but if he excels, he could work into standard leagues.

Loperfido is 26 years old and has already been with the Astros. He hit .236 and had a .299 average in 38 games with them in 2024. Loperfido had a .253 average and .296 OBP over 84 games with Toronto across two seasons.

Loperfido is also expected to be in a platoon role in Houston, so he's in a similar boat to Sanchez, just with not as much MLB experience under his belt.

I like Sanchez's fantasy outlook more for now, but Loperfido could also do enough to work into standard leagues eventually. Both outfielders are worth keeping tabs on as a result.