First base has been a glaring weakness for the Yankees over the last three seasons. Mark Teixeira had his last great season in 2015 — he hit .255/.357/.548 (143 wRC+) with 31 homers in 111 games that year — and Greg Bird helped picked up the slack after Teixeira went down with his shin injury that August. That was the last great year at first base in the Bronx.
From 2016-18, the Yankees had 20 (!) different players play at least one game at first base, two more than any other team. Among those 20 first basemen are Dustin Ackley, Billy Butler, Chris Parmelee, and pitcher Bryan Mitchell.