Fantasy Baseball First Base Draft Steal Candidates for 2025: Josh Naylor, Luis Arraez, Triston Casas and More

It’s time for another fantasy baseball draft steal candidate story. This time, we’ll go over some first basemen.

We’ve already looked at second basemen, third basemen and shortstops. Here’s the draft bust candidate story for first basemen, along with my top-10 fantasy rankings at the position in redraft and dynasty setups.

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1. Josh Naylor

Naylor is my No. 5 fantasy first basemen for 2025. He finished third at the position in 2025 and is now in a better fantasy situation with Arizona after an offseason trade. He’s usually the sixth or seventh fantasy first basemen drafted, and I think his ceiling is higher than that, as I could again see Naylor finishing as a top-three fantasy finisher. 

In 152 games with Cleveland last season, Naylor had a .243 average and .320 on-base percentage. Those numbers don’t really stand out, but his 31 home runs and 108 RBIs do. He also stole six bases and scored 84 runs.

It was a breakout season for Naylor, but there’s reason to believe he could be even better in 2025. He owns a career .262 average and .323 OBP, so a bump in average could lead to a great OBP.

Even if he doesn’t improve his average, the home runs, RBIs and runs scored are going to make Naylor a great fantasy hitter. He’s going to likely hit in the heart of the Arizona lineup, and hit after Corbin Carroll and Ketel Marte. Naylor is going to have the chance to drive in a bunch of runs, and it wouldn’t be all that surprising to have him lead the league in RBIs.

There’s some really high expectations for Naylor in Arizona, but so far, his draft hype hasn’t caught up. I’d take advantage of that and draft Naylor (even up to a round earlier than you see him listed elsewhere). He’s got draft steal written all over him, and could be the player to take your fantasy team over the top.

2. Christian Walker

Walker signed with Houston this offseason, opening the first base position for Naylor in Arizona. I think Houston’s offense took a step back this offseason, but it’s still got plenty of talent and should allow a masher like Walker to thrive in the cleanup spot.

Walker had a monster fantasy season derailed by a late-season injury last year. In 130 games, he hit 26 home runs and drove in 84 runs. Walker had a .251 average and .335 OBP, and he also scored 72 runs.

Despite being 33 years old, Walker still seems to have plenty left in the tank, and hitting in a lineup that includes Jose Altuve, Yordan Alvarez and several other notable names, Walker should be able to deliver a big fantasy season if he can stay on the field.

Walker likely would have been a top-10 fantasy first basemen if he didn’t get injured late last season. I have him as my No. 7 fantasy 1B, and think he could even finish higher than that. 

Walker is going around the same time in a draft as Naylor. I prefer Naylor by a decent amount, but Walker isn’t a bad alternative if you miss out on Naylor.

3. Luis Arraez

To the surprise of nobody, Arraez thrived after being traded from the Marlins to the Padres early last season. He went on to finish fifth among fantasy first basemen, and that’s without much power to his game.

I have Arraez as my No. 8 fantasy 1B this season, so I’m expecting a bit of regression. At the same time though, Arraez’s average draft slot is so low that he’s a huge fantasy draft steal candidate.

In 150 games last season, Arraez hit .314 and got on base at a .346 clip. He hit four home runs and drove in 46 runs. Arraez stole nine bases and scored 83 runs.

He’s a career .323 hitter with a .372 OBP, so you can say all you want about his lack of power, because those two marks make him a great fantasy asset. Arraez continues to deliver year after year as well, so I really don’t understand why his draft stock is never that high.

He’s still just 27 years old, and probably has some fantasy position versatility too. What’s not to like?

Sure, in a category league, Arraez isn’t going to help you much in the home run or RBI department, but a high average, OBP and run scored amount are three major categories where he’ll help a bunch. Add in he can maybe be started in a few different slots and Arraez is a super valuable fantasy player.

When I end up drafting Arraez, I always try to pair him with a power-hitting first basemen. That way, the two can combine for some monster numbers, and you don’t lack in any areas.

Arraez is a fine fantasy option as a No. 1 first baseman. If you can get him as a secondary option, your fantasy team could be in store for some big things.

4. Triston Casas

Casas barely missed my top 10, but that’s really because he hasn’t shown us a full season yet. He’s got a chance to be a top-end fantasy first basemen if he can simply stay on the field for a whole season.

He’s played 222 games over his first three MLB seasons. Casas got in just 63 games last year. He owns a career .250 average and .357 OBP, so those numbers alone show you how great he could be.

His 162-game averages are 31 home runs and 80 RBIs, along with 77 runs scored. Those kinds of numbers at an already weak fantasy 1B spot means Casas could be a top-five finisher by the end of the season.

Durability is definitely a concern though, but that’s also keeping his draft average slot somewhat down. He’s still a top-100 pick to most people, but he has top-end fantasy potential, so I get it.

Really, Casas is a big draft steal and bust candidate. If he can stay on the field, he’s going to have a great chance at being one of the top draft steals from this season. If he’s banged up and misses extended time again, Casas might be one of the bigger busts.

Regardless of how you think his season is going to go, protecting him with another fantasy 1B would be a wise move.

5. Carlos Santana

Santana is a deep, deep sleeper. I often don’t see him being ranked in the top-250 players in 2025 rankings. He’s likely to go undrafted in a bunch of standard leagues.

That’s pretty wild to me considering Santana nearly was a top-10 fantasy 1B last year. He could be a big-time waiver pickup for 2025 if his draft stock doesn’t improve between now and the season.

Despite being 38 years old (39 by the end of the season), Santana has been durable. He played in 150 games last season, and has played in at least 131 games in all but two seasons in his 15-year career (COVID season and his rookie year).

Last year, Santana had a .238 average and .328 OBP. He clubbed 23 home runs and drove in 71 runs. He scored 63 runs and even stole four bases.

He’s expected to replace Naylor at first base for the Guardians. He should slot into a middle-of-the lineup spot, and there’s plenty of talent around him to have a good/great fantasy season.

I get that you don’t want to put a ton of faith in a 38-year-old, but at his draft average slot, he’s definitely worth it. Draft him as a backup fantasy 1B, and he’s probably going to be playable most days as an extra infielder or utility player.