Triston Casas for the Mariners?
Add another name to the Mariners' hot stove pile.
About a week ago, I identified eight potential first base candidates for the Mariners. I can’t recall why Triston Casas of the Red Sox didn’t make my cut. In hindsight, perhaps Casas should’ve been discussed.
I say this because someone on social media suggested Casas after I published my piece, which made me question whether I whiffed by not discussing the Boston first baseman. I’d give the person credit by name, but I couldn’t find their post.
Not only that, Adam Jude of the Seattle Times recently mentioned Casas as a possibility if Seattle’s front office wanted to make a splash in the trade market. Adam also cited Casas’ name when talking to fellow Mariners beat writer Ryan Divish during the latest edition of the Extra Innings podcast.
Since we’re about three weeks from Thanksgiving and it’s getting darker earlier every evening, why not fire up the hot stove and talk about another acquisition idea for the Mariners?
One more thing before we dig in. I have no clue about the kind of trade package it would take for the Mariners, or any team, to pry away Casas from the Red Sox. I could act like I know what it would take, which some folks in the blogosphere and on Twitter tend to do. But let’s face it, they probably don’t have a clue either.
Okay, let’s talk about Casas the player. Since a rib cage injury limited him to 63 games and 243 plate appearances this year, I took a different approach than usual and consolidated his 2023-24 numbers to give us a bigger sample size to consider.
Selling points: Among 230 hitters with 700-plus plate appearances over the past two seasons, Casas is top-35 in multiple run production categories.
MLB Rankings of Casas’ 2023-24 Stats
HR% (21st in MLB)
BB% (10th)
SO% (190th)
AVG (103rd)
OBP (28th)
SLG (32nd)
wOBA (26th)
wRC+ (33rd)
Hard-hit% (51st)
Barrel% (27th)
To further provide a sense of Casas’ stature among the best offensive weapons in baseball, here are a few nerd nuggets for your consumption.
Casas’ walk rate tied for tenth-best with Kyle Tucker of the Astros. His SLG tied with Pete Alonso, formerly of the Mets. As many of you know, the two-time Home Run Derby champion is a highly-desired free agent target for some Seattle fans.
The 126 wRC+ produced by Casas tied him with Red Sox teammate Jarren Duran and Isaac Paredes of the Cubs and was essentially the same as another free agent coveted by some followers of the Mariners - Anthony Santander (124). The left-handed hitter’s wRC+ was also better than several notable names, including Alonso, Fernando Tatis Jr., Alex Bregman, J.D. Martinez, and Josh Naylor.
Weighted Runs Created Plus (wRC+) quantifies how a hitter’s total offensive value compares with the league average after adjusting for park effects. League-average is always 100. Therefore, a wRC+ of 150 means a hitter was 50-percent more productive than the average player. An 80 wRC+ would be 20-percent below average.
Casas’ superb hard-hit and barrel rates tell us making loud, quality contact was a specialty for him. From a somewhat more conventional perspective, he hit home runs at the same rate as Adolis García, Kerry Carpenter, J.D. Martinez, and Shea Langeliers did.
Casas finished third in 2023 AL Rookie of the Year voting behind winner Gunnar Henderson and runner-up Tanner Bibee. Among rookies, the American Heritage High School product ranked third in OBP, fifth in SLG, and fourth in wRC+.
Fun fact: Current Mets third baseman Mark Vientos and one-time All-Star Eric Hosmer are graduates from the same high school Casas attended. Vientos was drafted a year prior to Casas.
Potential concerns: Well, Casas did miss nearly four months of the 2024 season. He was also sidelined for the final two weeks of the 2023 campaign with shoulder inflammation. To be clear, I’m not implying the 24-year-old is injury-prone or anything like that. But I do feel compelled to share everything I notice that may be relevant to our conversation.
Within the group of 230 hitters cited above, only 40 had a higher strikeout rate than Casas did.
Statcast doesn’t care for Casas’ defense. Over the last two seasons, he accrued minus-12 OAA. Among 37 qualified first baseman, only Josh Bell (minus-13), Ty France (minus-13), Andrew Vaughn (minus-16), and Vladimir Guerrero (minus-22) were rated worse than the Floridian.
Outs Above Average (OAA) is a range-based metric that shows how many outs a player has saved.
It’s unlikely Casas will ever be considered a speedster. His 24 ft/sec sprint speed was fourth-slowest among 404 players with 50 competitive runs this year. Someone might suggest the rib cage injury affected him. But it’s important to note he had a 24.9 ft/sec sprint speed last year.
Thoughts: A hitter with a lot of swing and miss like Casas can still be valuable provided he’s productive at the plate when not striking out. After all, Cal Raleigh had a 28-percent strikeout rate this year and I don’t recall many Mariners fans griping about it. Perhaps the 26th overall draft pick in 2018 can be similar to Raleigh in this respect.
As for those unsightly defensive metrics, I'll point out that most of Casas’ minus-12 OAA was accrued in 2023. Yes, his playing time was limited in 2024 and OAA is a counting stat. But his minus-2 OAA this year sounds much more palatable than the minus-10 OAA tallied the season prior.
Besides, the Mariners have demonstrated a core competency of being able to help skilled, motivated infielders improve their glove work. J.P. Crawford, Eugenio Suárez, and Josh Rojas are recent examples of fielders who’ve thrived after joining the organization.
A player with Casas’ superb on-base ability and potential 30-home run power would be a great acquisition for any club, including the Mariners. This assumes the Red Sox are interested in dealing him.
Yes, Casas has issues worthy of mention. But we should remember he’s 24 and has appeared in just 222 big-league games. So, there’s still plenty of time to soften those blemishes and further develop this talented player.
My Oh My…