The Pirates entered this offseason needing to conjure up a solution at first base. They received suboptimal production at the position from their rotating cast of characters throughout the year, and by season’s end, they were without a primary first baseman entirely. Less than a month into the offseason, the club possesses the depth that it previously lacked.

First baseman Carlos Santana has signed a one-year deal with the Pirates that the club announced on Tuesday, and he stands to complement the recently acquired Ji-Man Choi to form a platoon at first base. The deal is worth $6.725 million, a source told MLB.com.

Santana, 36, hit .202/.316/.376 with 19 home runs and a 102 wRC+ across 131 games with the Royals and Mariners. On the defensive side, Santana accumulated four defensive runs saved and three outs above average in 76 games at first base.

Along with his on-the-field contributions, Santana, who will be the Pirates’ most experienced player, has been lauded as a clubhouse leader and played an instrumental role in the Mariners reaching the playoffs for the first time since 2001.

With Choi and Santana, the Pirates now have a first-base tandem that can provide offense against righties and lefties.

Choi, a left-handed hitter, has fared better against righties in his career (.810 OPS) than lefties (.589). Santana, a switch-hitter, has slightly more even career splits, but has hit better against lefties (.819 OPS) than righties (.777). In 2022, Santana posted a .789 OPS against left-handers and .655 against right-handers.

Santana could be one of several players who benefit from the removal of the defensive shift in 2023. Last season, Santana saw a defensive shift in 98.3 percent of his plate appearances as a left-handed hitter, a mark that led MLB.

While Santana, who owns a career .791 OPS, didn’t have his best offensive season in 2022, his peripherals were encouraging. Santana ended last season in the 81st percentile of average exit velocity, 87th percentile of chase rate and 88th percentile of expected weighted on-base average. Santana remained one of baseball’s most patient batters as well, finishing tied for fifth among all qualified batters with a walk percentage of 14.0.

Choi and Santana will help provide offense to a Pirates team that did not receive much offensive production from their first basemen last season. Across 636 plate appearances, Pittsburgh’s first basemen hit .206/.264/.337 with 17 home runs and a .601 OPS. 

At the beginning of November, the Pirates didn’t have a first baseman on the 40-man roster. Now, they have three. In addition to acquiring Choi from the Rays in exchange for Minor League pitcher Jack Hartman in early November, the Pirates also claimed slick-fielding Lewin Díaz off waivers from the Marlins earlier this week.

Díaz is still finding his footing on offense at the Major League level, owning a career .567 OPS across 343 plate appearances, but the 26-year-old’s defense has already proven elite. In 99 career games, Díaz has 16 defensive runs saved and nine outs above average. For context, Christian Walker, who won the Gold Glove at first base in the National League, has 17 defensive runs saved and 14 outs above average in 150 games. 

As December nears, Pittsburgh’s Opening Day infield is beginning to take form. Choi and Santana will platoon at first base. Ke’Bryan Hayes and Oneil Cruz compose the left side of the infield at third base and shortstop, respectively. With Kevin Newman having been traded to the Reds last week, Rodolfo Castro is positioned to be Pittsburgh’s everyday starting second baseman.

With first base addressed, Pittsburgh’s attention should shift to acquiring an everyday catcher. Currently, the only two backstops on the Pirates’ 40-man roster are Endy Rodriguez, the Pirates’ No. 6 prospect per MLB Pipeline, and Ali Sánchez. Rodriguez likely won’t be on the Opening Day roster and Sánchez only has seven Major League games to his name. Luckily for Pittsburgh, there is no shortage of veteran backstops on the open market, including names such as Roberto Pérez, Austin Hedges and Tucker Barnhart.