The Philadelphia Phillies need to decide what to do at the catcher position this winter. They are attempting to re-sign J.T. Realmuto to a short-term deal. The veteran has been an integral part of the Phillies' core since they acquired him in a trade with the Miami Marlins in February 2019.
Realmuto is the best backstop available in free agency this offseason, and other clubs have an interest in signing him (subscription required). If Realmuto doesn't return, president of baseball operations Dave Dombrowski may look to acquire a younger starting catcher via trade. One alternative could be the Houston Astros' Yainer Diaz.
Astros catcher Yainer Diaz is an ideal trade target for the Phillies if they don't re-sign J.T. Realmuto
MLB.com's Mark Feinsand recently listed Diaz as a potential Astros trade candidate. He finished with 20 home runs, 70 RBIs, and a line of .256/.284/.417 with a .701 OPS in 143 games this year.
The 27-year-old has displayed his offensive talent since 2023 with the Astros. In his first full MLB season two years ago with Houston, Diaz compiled 23 home runs, 60 RBIs, and slashed a .282/.308/.538 line with an .846 OPS in 104 games. His 23 home runs remain his highest in a single season.
Diaz finished with a career-high 84 RBIs in 2024 with 16 home runs and a career-best 29 doubles, with a .299/.325/.441 slash line and a .766 OPS in 148 games.
According to Feinsand, while Diaz has displayed solid offensive ability so far in the majors, his defense needs improvement. The Astros catcher ranked in the 28th percentile in blocks above average and in the 18th percentile in framing.
YAINER DIAZ. GRAND SLAM. pic.twitter.com/ZtwN9BxESa
— Houston Astros (@astros) April 12, 2025
Diaz wouldn't come cheap in a trade, as he still has two more years of club control remaining following 2026. He's projected to earn $3.5 million next year, according to Spotrac, so his salary will be far less than what Realmuto is projected to earn in free agency.
Realmuto is still is a viable starting catcher. However, unlike Diaz, he's declining offensively as he is in the final years of a successful career. Aside from the shortened 2020 season, his 12 home runs this season were his fewest since 2016, and his .699 OPS was his lowest in 10 years.
The 34-year-old finished with a slash line of .257/.315/.384 and 52 RBIs in 134 games in 2025. Realmuto was active for about the same total number of games back in 2023. The former third-round pick totaled 20 home runs, 63 RBIs, and slugged a .252/.310/.452 line with a .762 OPS in 135 contests, in comparison, providing proof of his gradual decline as a hitter.
The Phillies would also have their starting catcher for at least the next three years if they traded for Diaz. Many projections have Realmuto agreeing to a new contract that will only be for the next two seasons. If Philadelphia re-signs the veteran backstop, they will need to address the position again at some point to find another younger replacement.
If the Phillies ultimately decide to get younger at catcher this offseason by not re-signing Realmuto, Diaz is one option in his prime who could provide a reliable bat for a lineup that possesses plenty of veterans like Bryce Harper, Kyle Schwarber, and Trea Turner.