'I actually want them to steal': Mack's 4-hit night the cherry on top of elite defense

MIAMI – Marlins rookie catcher Joe Mack's game-changing defense factored into him taking a pivotal at-bat during Tuesday night’s 10-6 victory over the D-backs at loanDepot park.

Wait, what?

After the Marlins’ bullpen coughed up a three-run lead in the top of the eighth, manager Clayton McCullough stuck with the left-handed-hitting Mack despite southpaw Brandyn Garcia taking the mound in a 6-6 ballgame.

“Tough call there, leading off an inning,” McCullough said. “That's a big moment in that game [with] how this thing might end up going. What he is able to do defensively is such a key for our team right now. Certainly weighing the offensive potential upgrade in that at-bat versus defensively what comes down.”

Mack, who ranks as MLB Pipeline’s No. 41 overall prospect, rewarded McCullough’s trust with his career-high fourth hit. At 23 years and 164 days old, he became the youngest catcher in franchise history to achieve that feat. Three batters later, Major League hits and average leader Otto Lopez singled to score Mack in what would become the decisive four-run inning.

Things might’ve played out differently if Mack, the 2024 Minor League Gold Glove Award winner, hadn’t been living up to his reputation.

Earlier on, Mack fired a throw that allowed Xavier Edwards to apply the tag on potential basestealer Geraldo Perdomo’s leg for the final out of the second. In doing so, Mack became the 13th MLB catcher with double-digit caught stealings – and in far fewer games (28) than his peers.

Though Mack did commit a passed ball – his fourth – in the seventh, his successful ABS challenge in the sixth changed the complexion of the frame. With two inherited runners on, righty Anthony Bender fell behind to Ryan Waldschmidt. When his next pitch got called a ball, Mack got it overturned. Bender would go on to strike out Waldschmidt, and then fan LuJames Groover to escape the jam.

“He's got his feet wet now, and he's been challenging good, too,” said righty Max Meyer, who allowed two runs over 5 1/3 innings. “He knows the game, he's able to hose runners. It's awesome having a guy back there that can do that, and takes off a lot of pressure for the pitchers, too, in innings, when you know that if they steal, there's a really good chance that he's probably going to get hosed.”

Thanks to two scheduled off-days, McCullough has been able to optimize the position’s defense and start Mack at catcher in seven consecutive games – matching the most for any Major Leaguer this season (William Contreras and Logan O’Hoppe).

Just Mack’s presence has made a considerable impact. Here are the collective backstop numbers for Miami:

Before Mack’s debut on May 4:

– 45 steal attempts against (most in MLB)
– 42 steals against (most in MLB)
– 93.3% stolen-base percentage against (second-worst)

Since Mack’s debut:

– 35 steal attempts against (sixth-most)
– 23 steals against (T-11th)
– 65.7% stolen-base percentage against (sixth-best)

Baserunners are 16-for-26 (62%) against Mack, which gives him a 38 percent caught stealing rate. League average was just 24.3 percent entering Tuesday.

“I actually want them to steal,” Mack said. “I'm hoping that they steal. I'm like, ‘Please run, please run.’ It's probably my favorite part of my game, and I know my ability to throw people out, and get a guy off scoring position, and save the pitchers some pitches, and help him go out there for the next inning [is my thing]. It's a lot of fun being able to do that, and I genuinely want them all to run, and have that part of my game show, so it's pretty cool.”

It’s an added bonus that Mack’s at-bat quality of late is complementing his defense. Since the start of the series in Washington, he is 9-for-23 (.391) with one double, his first homer and seven RBIs. Prior to this stretch, Mack was 13-for-64 (.203) with three extra-base hits and six RBIs to open his career.

Mack credits trusting his eyes and hands. Approach-wise, he’s not coming off the fastball.

“We all knew he's a talented offensive player, and once he got 20-25 plate appearances under his belt, we've just seen some of the aggression toned down and it be placed in more appropriate places in the zone that he should be swinging at,” McCullough said.

Added Mack: “It's been going good for sure. Definitely dialed in the approach and what I'm trying to do at the plate. Things have been coming together, hits have been falling, and putting good swings on balls. I was very happy to hit in that eighth inning and get the guys going, and get a nice leadoff knock for him.”