First base defense doesn’t get a lot of credit. It seems easy enough — stand there and catch the throws from your teammates, and maybe field a grounder and then carry it a few feet to the base. You could never make a throw and still get your job done adequately, and no one would fault you.
Of course, there’s a lot more to any MLB position than that, even though first base is squarely on the easier and less valued end of the defensive spectrum. And even though the threshold is lower for entry, with slugging DH types usually able to at least hold their own there well enough to keep their bats in the lineup, a great defender can truly make an impact.