4 - Brendan Donovan
After bursting onto the scene as an unknown rookie in 2022, Brendan Donovan immediately made an impact as a super-utility defender, beating out teammate Tommy Edman for the first-ever utility Gold Glove Award. Donovan fits the definition of a "spark-plug" player perfectly, as he's played solid defense at every position aside from center field and catcher. His offensive tools shouldn't be taken lightly either. He slashed .281/.394/.379/.773 during his rookie campaign, finishing 3rd in Rookie of the Year voting.
This past off-season, Donovan worked on generating more bat speed and power. After starting off 2023 slowly, Donovan bounced back in a big way, slashing .284/.365/.422/.787, successfully increasing his power without sacrificing his batting average. Despite playing 31 fewer games in 2023, Donovan slugged 6 more home runs.
Josh Jacobs broke down Donovan's successes at the plate in a separate article noting his torrid stretch from May 21 through the end of July. He slashed /316/.395/.489/.884 for a 145 wRC+, tied for 17th in all of baseball. Sure, those numbers probably aren't sustainable, but it's a sign of what's to come. The Cardinals' lineup is much better when Donovan is healthy.
Sadly, Donovan's elbow injury leaves him a bit lower on the list, as it has thrown his future as a super-utility defender into question. If Donovan is restricted to DH for some time as he recovers, his value will dip significantly. With this injury, Donovan might be more inclined to take an extension but the Cardinals might be less inclined to offer him one. On the bright side, the Cardinals' rough stretch allowed the team to shut him down early to rest and recover. Hopefully, we will see a fully healthy Brendan Donovan come this Spring.