‘Love you, Boston': Mariners' No. 13 prospect thrives against old friends in the desert

PEORIA, Ariz. –- When you’ve traveled as much as Boston Smith has in 2026, you’re bound to bump into old friends. 

The Mariners’ No. 13 prospect did that twice in the Arizona Fall League on Wednesday, facing White Sox right-handers Mathias Lacombe (who he caught 10 times in the Chicago system before a Trade Deadline move) and Jonathan Clark (who he caught five times this summer). He got the best of Lacombe with a fifth-inning double -- his second of the game -- on a 106.8 mph, 411-foot shot to dead-center field.

“After I got on second, I peeped over at him, and he's just laughing at me,” Smith said of the White Sox No. 17 prospect. “We had a very short moment where we kind of just said, ‘Yeah, I got you.’ It was fun.” 

One frame later, Clark exacted a measure of revenge, getting the left-handed-hitting Smith to whiff on three changeups during a five-pitch strikeout. 

“The first thing he says,” Smith said, “he's like, ‘Love you, Boston.’” 

Still, it was Smith’s Peoria side that got the final laugh in an 11-9 win over Glendale at Peoria Sports Complex. The 23-year-old catcher/outfielder, who started behind the plate, finished 2-for-3 for his first multihit day and his first two extra-base hits of any kind through 14 games of Fall League play.

A sixth-round pick out of Wright State by the Nationals in 2025, Smith was traded to the White Sox straight up for Major League infielder Curtis Mead on March 28 -- just before he could be sent out to a Washington Minor League affiliate. He climbed three levels of the Chicago system from Single-A to Double-A, only to be traded again as part of the package that sent Luis Castillo from Seattle to the South Side. 

Smith's 2026 numbers signaled a major breakout for the collegiate senior pick who signed for only $50,000: a .274/.424/.566 line and 31 homers across 493 plate appearances. His 158 wRC+ was fourth-best among Minor League full-season qualifiers. The Mariners still approached him weeks after the second trade about going to Arizona with the goal (among many) to keep getting catching work.

Now with Peoria, Smith carries with him hitting knowledge and buzzwords from three different farm systems. 

Of the Nationals, those that came to mind were routine and buy-in. 

“I won't let somebody just totally reinvent my swing,” Smith said. “But I will let them work on little bits and pieces of my swing itself to adjust because as I go up in levels, as I change and go to different leagues, pitching stats change, approaches change, the body obviously fatigues. I have to make adjustments to compromise to what my body's responding to.” 

That concept carried over to the White Sox, who continued to hone that adjustability in Smith’s introduction to pro ball that may have directly led to Wednesday’s success.

“Just understanding that I have a very vertical bat path, they put me in environments to flatten my swing out,” Smith said. “I kind of actually went back to that a little bit today. I had a good conversation with our hitting coach today and said, ‘Hey, I think working on a pitch that's starting from the ground up is going to allow me to flatten my swing out.’ I did that today in the cage and the results showed. I finally stayed behind baseballs. A couple days ago, I’m swinging underneath those pitches.” 

His time with the Mariners has been defined by culture and communication, including a system that uses a “Rake” score to help hitters understand their strengths and weaknesses. 

“It essentially puts a lot of variables into play that define, ‘OK, did I hit the ball hard, did I get the right pitch and how well have I made contact with it?” Smith said. “[I’m] buying into the play hard [mentality], swinging at the right pitches and just being a student of the game. They're really good at helping players understand what it means to develop without putting a big stamp on a player.”

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Balancing those messages could create confusion or it could give Smith a broader education base for his career moving forward. It could give him ways to break out of a Fall League slump, as he did Wednesday. (He’s now 7-for-45 through 14 games in the desert.) 

At the least, it’s given him a unique experience to carry into his second, perhaps more restful, offseason. 

“Not a lot of players can say they got traded twice and get to play in the Fall League in their first full season,” Smith said. “[I’ll] just sit back and don't hang on to the bad that's happened so far here in the Fall League, but remember and process the good. ... Keep working, keep growing, and just see what happens.”