Colorado Rockies infielder Brendan Rodgers shot a 104 MPH line drive to the right side of the Arizona Diamondbacks’ infield with a runner on second while down 1-0 in the sixth inning on July 10.

D-backs first baseman Christian Walker dove to his left and snagged the baseball to save the game-tying run from scoring at Chase Field.

The web gem was among a growing number of highlights in a career defensive season for Walker, who entered Monday with 13 defensive runs saved, the most by a first baseman this year, according to FanGraphs.

The @Dbacks are putting on a defensive clinic! Christian Walker saves a run with this play. pic.twitter.com/nw5O0h0Jpu

— Bally Sports Arizona (@BALLYSPORTSAZ) July 10, 2022

His previous career-best was nine in 2019.

Walker’s preparation has evolved to cover any ball hit his way at real-time speed. Hand-eye coordination and glove accuracy are some of his areas of focus, which came into play during that diving catch and this snag:

“Getting the reps but fast reps, game-speed reps, intense,” Walker said. “Even I feel like there’s an angle that I can take some ground balls for a little bit and as I get tired and get winded, those reps are the ones that are important because that’s the feeling in the game when the heart rate is up.

“You’re trying to slow down the moment. I think the key for me is fast, hard intent-filled reps.”

Walker trains during the offseason at the University of South Carolina, where he played college ball. He takes ground balls there, sometimes fielding hot shots off a pitching machine.

Walker said he fields grounders upward of 100 miles per hour, turning the three knobs on the machine all the way up and angling it down to mimic the sharpest grounders. He also fields knuckleballs to work on awkward bounces and uncomfortable angles.

“That’s kind of the point of practice, to make it so the environment makes you better,” Walker said.

The results have shown. No other first baseman in MLB has half of Walker’s defensive runs saved, as Vladimir Guerrero Jr. owns six to pace the rest of the field.

Only third basemen Nolan Arenado of the St. Louis Cardinals and Ke’Bryan Hayes of the Pittsburgh Pirates have more in all of baseball with 15 each.

Walker’s ultimate zone rating – which takes a player’s arm, range, errors and double play run above average into consideration – also tops MLB first basemen at 3.2, according to FanGraphs.

“He’s steadily improved every single year,” manager Torey Lovullo said. “I see somebody that’s working extremely hard in pregame and never takes days off on that side of the ball. If we’ve got the ability to take ground balls, he is one of the first ones out there and working at a full, very crisp pace.

“He practices fast and I think that translates into success in the games. He’s having a terrific year defensively, but it’s not a surprise to me. He’s worked his butt off to get there.”

The veteran’s method involves more fine-tuning during the offseason so he can focus on gaining consistent game-speed reps when spring training and the season roll around.

Walker, who played catcher and third base growing up before settling into first base during college, said he doesn’t question himself on the field as a result of that preparation.

He has been a Gold Glove finalist once in his D-backs tenure (2019). Walker finished as a runner-up to the Chicago Cubs’ Anthony Rizzo but is making a strong case for awards season this year.

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