MILWAUKEE – Have the Giants finally entered the modern era?

Will they finally take advantage of Major League Baseball’s new rules that encourage base stealing and aggressive base running?

Do they finally have a guy who’s a legitimate threat on the bases?

Can Jonah Cox be a difference maker?

“One hundred percent,” beamed Bryce Eldridge, who saw Cox run wild when they were teammates on two minor-league teams in 2024.

There are plenty of reasons for the Giants’ abysmal season, and base running makes the laundry list. Not just the mistakes on the paths but the lack of overall team speed, a reason the Giants rank last in the majors in stolen bases and last in base running runs above average, Fangraphs’ all-encompassing metric.

Cox is on the roster to boost the running game and, in turn, boost the offense.

But here’s the thing. You can’t expect results with the dude on the bench.

Cox got his first taste of the big leagues Sunday in Colorado and his first start Monday in Milwaukee. But after just one at-bat, he was pulled for a pinch-hitter. The Giants were trailing 8-2 at the time and ultimately got boatraced 16-2, the season’s most lopsided loss.

Why did manager Tony Vitello remove Cox, one of the fastest men in pro ball, who was hitting .400 for Double-A Richmond, the highest batting average in any league, from A-ball to the majors, and could be a key piece to the Giants’ future depending on how well he adapts to the big leagues?

Vitello said it wasn’t because Cox crashed into the quirky center-field wall at American Family Field trying to backhand Brice Turang’s towering triple during the Brewers’ seven-run second inning — even though Cox’s upper body was wrapped in ice after the game.

It was because the Brewers replaced their left-handed starter, Shane Drohan, with a right-handed reliever, Chad Patrick. Seeking a platoon advantage to begin the fifth inning, Vitello pinch hit Drew Gilbert, who flied out.

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“Obviously, it came a lot quicker than we thought it would,” Vitello said of the Brewers’ starter coming out of the game. “Hoping to get the leadoff man on and punch back as quick as possible with what the score was.”

Does that mean Cox will play only against lefties?

“Not 1,000 percent,” Vitello said. “That would be the favorite. Also off the bench, running the bases, and then defense late in the game, too. Multitude of ways to get in, but facing a right-handed pitcher isn’t out of the question.”

After the game, Cox insisted he wasn’t hurting from smacking into the wall — “It’s nothing crazy, we’re good” — and vowed to be available Tuesday. The Brewers are starting old friend Kyle Harrison, a lefty, which could give Cox a path back into the lineup.

“Looking back,” he said, “I probably should’ve played it off the wall. But I thought I had a chance off the bat, so I was trying to go for it.”

Giants pitchers surrendered 18 hits and issued 11 walks. Landen Roupp was charged with eight runs and pitched with back tightness but didn’t tell the coaching staff or medical team. If that wasn’t bad enough, position player Buddy Kennedy (called up from Sacramento early Monday) pitched the eighth inning while catcher Daniel Susac played third base. The only highlight was Matt Chapman’s first homer since March. Meantime, the Giants will be bringing in veteran third-base coach Gary Pettis, an Oakland native, to replace Ron Wotus, who took over in the interim for reassigned Hector Borg.

Before the game, I asked general manager Zack Minasian if Cox’s speed can help make him carve out a role with this team.

“Over time, absolutely,” said Minasian, noting Cox also is a premier defender anywhere in the outfield. “I wouldn’t want to put it on him to feel like he has to do it right now. But if he’s on the bases, his speed is going to be impactful.”

The Giants are desperate for such a speedster. Consider that their fastest runner, according to Statcast’s sprint speed metrics, is Casey Schmitt.

Now consider that Schmitt, whose sprint speed is 28.2 feet per second, is tied for 109th in the majors.

And now consider that Cox pinch-ran Sunday, scored all the way from first base on Rafael Devers’ single to center (the Rockies kept making throwing errors), and reached a 30.1-feet-per-second sprint speed.

How quick is 30.1? Only four big-leaguers’ average sprint speed rank higher. Bobby Witt Jr., Eli White, Jorge Mateo, and Henry Bolte.

Yeah, quick.

“He’s the fastest,” Eldridge said. “I mean, he’s the reason I got some stolen bases that year. He’d be on second, I’d be on first. He’d steal third, and I got to sneak in behind him. Definitely good person to have in your lineup. An intriguing player for us.”

It’s such a new and refreshing element that has been missing from the Giants’ offensive arsenal in recent memory. The last Giant to steal 40 bases in a season was Barry Bonds in 1996. Last to swipe 30 was Dave Roberts in 2007. In the past decade, just one Giant has even stolen 20 bags, Thairo Estrada.

The Giants have a lot of catching up to do, but Cox could be a start if given the chance. He stole 163 bases in the minors in 192 attempts, an impressive 85% success rate. But he has to stick around.

Remember Bryce Johnson? In spring training 2023, he swiped 12 bases in 12 attempts, and the Giants were talking about finally implementing a running game. That didn’t work out. Now a Padre, he has just 12 big-league steals to his name.

Remember Tyler Fitzgerald and Grant McCray? There were debates in spring training last year over who was faster? Well, Fitzgerald is in the Dodgers’ farm system, and McCray remains at Triple-A Sacramento.

The Giants would love to run like the Brewers, who rank way down in payroll (20th out of 30 teams) and are forced to find creative ways to produce runs because they don’t go out and buy the top free-agent hitters every winter. One way is getting athletes who can run the bases extremely well. Based on sprint speed numbers, the Brewers have eight players faster than the fastest Giant, at least before Cox’s arrival.

On Feb. 2, 2024, the Giants acquired Cox from the A’s, largely so they could move Ross Stripling’s contract to Oakland. The rebuilding A’s needed starting pitching and had a miniscule payroll, so they took on the veteran starter plus $9.25 million of his $12.5 million contract — the Giants ate the remaining $3.25 million.

Cox wasn’t a premier prospect. MLB.com (opens in new tab) ranked him No. 28 among A’s prospects, but he hit and ran himself all the way to the big leagues as a Giant.

“It’s impactful, game-changing speed and defense,” said Minasian, who credited both Cox and the player development department for his improvements at the plate including better strike-zone awareness. “We liked him going back to the [2023] draft. The tools have always been there, and we’re seeing more and more skills starting to develop.”

Now it’s a matter of getting the chance to show them off.