ST. LOUIS -- The Cubs got off to a promising start on Saturday night, bunching four singles in the first inning to score three runs off Cardinals ace Adam Wainwright four days after Wainwright’s 41st birthday. The key shot was a line drive to right field off the bat of Rafael Ortega to score Ian Happ and Nico Hoerner.

But Paul Goldschmidt, the front-runner for the National League MVP Award, hit his 34th home run in the bottom of the first to make it a one-run game. Then back-to-back home runs from Tommy Edman and Tyler O’Neill leading off the third gave St. Louis the lead. The Cardinals poured it on that inning, with Yadier Molina’s three-run double salting it away early for St. Louis, which went on to win 8-4 in front of 47,816 at Busch Stadium.

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Power is one of the real separators between the two age-old rivals: The first-place Cardinals are third in the Majors with a .429 slugging percentage. The third-place Cubs are middle-of-the-pack at .390.

Many of those Cardinal fans in a sellout crowd came to see Albert Pujols hit his 695th home run. He didn’t, though Happ caught a deep Pujols drive at the base of the left-field wall in the first inning. The fans seemed to revel in the Cubs’ misery after that, as they tend to do here.

The Cubs are coming off their best month -- they went 15-15 in August -- but unless they finish this season by winning at least 15 of their 29 remaining games, they’ll finish worse than last season’s 71-91 record. That makes the rest of this season all about evaluating the roster to decide who they want to keep and where they can upgrade.

One of those Cardinals home runs drew the attention of one of the Cubs’ most promising young players. Hoerner and Edman were double-play partners at Stanford in 2016. Edman, a junior at the time, played shortstop. Hoerner, a freshman, played second base. After Edman was drafted by the Cardinals, Hoerner moved back to his natural position, shortstop.

He’d like to follow Edman in another regard: gradually gaining power to go with the strong baseball skill set that got him to Stanford and professional baseball in the first place.

“The way our program was run, it was really all about contact,” Hoerner said. “[Edman] was a guy who has elite contact skills and runs well. In pro ball, he kind of found his stride in terms of driving the ball. It’s nice to see him develop that part of his game as well.”

Hoerner, 25, has been the Cubs’ best player this season by Baseball Reference’s version of WAR, with his 4.1 bWAR edging Happ’s 3.7. Much of Hoerner’s value has been built on his excellent fielding at shortstop. He and Edman are both top four in the Major Leagues in outs above average.

The Cubs simply are waiting on Hoerner’s power to blossom as it has for Edman, who has hit 13 home runs this season for St. Louis, including one in each of the first two games of this series. Edman also smacked 41 doubles in 2021. What separates them is far from unbridgeable: Edman’s career slugging percentage is .410. Hoerner’s is .379. With the granular way in which players are evaluated nowadays, differences at the margin matter.

“In terms of being gritty players, yes, of course there are some similarities there,” Cubs manager David Ross said. “I don’t enjoy talking about guys from other teams, but the similarities exist. They’re both baseball rats who live and die with it. I don’t know Tommy at all, but he seems to be a guy who doesn’t give away at-bats, takes pride in his defense, plays all over the field and takes extra bases. Nico has a lot of those characteristics as well.”

After playing multiple positions in his first three seasons, Hoerner has found a home at shortstop after the departure of Javier Báez last July. Dansby Swanson is the only shortstop with more OAA than Hoerner’s 15 this season. Hoerner is also having his best offensive season since his big league arrival in 2019, with a .283 batting average and .730 OPS.

Hoerner said his greatest improvement this season is in “stuff that doesn’t show up in a lot of the metrics,” such as his ability to turn double plays, make skillful tags and relays and to be in the right place for shifts. He credits Báez for helping demonstrate how to do many of those things and Cubs bench coach Andy Green for working with him on improving his infield defense.

“As a teammate, the thing that stood out about Javy is, for all of his flash and excitement, there was a lot of thought to what he did,” Hoerner said. “He was always thinking a couple steps ahead, kind of playing that game, whether it was baserunning or defense. There’s a reason behind a lot of the greatness you see. You’re like, ‘Wow, what amazing instincts,’ but it’s really rooted in a very smart baseball mind.”

The Cubs have another strong baseball mind on their hands, it would seem. Ross raved about Hoerner’s work ethic and leadership skills as a young player. Next, if he can just pick up on some of the power older players like Báez and Edman have developed, Hoerner could be someone this team builds around for years to come.