ST. LOUIS -- Most 35-year-old catchers playing their 14th big-league season would be fading like the September sunlight.

Not Yadier Molina, not this September. The St. Louis Cardinals veteran has knocked in 10 runs the past three games, giving him 75 RBIs for the year, just five off his career high set in 2013. He has 17 homers, the second-best total of his career.

Molina was strong again Tuesday night with three RBIs in the Cardinals' 13-4 rout of the Cincinnati Reds. He figures to be back in the lineup Wednesday night for his 126th game of the season in the second contest of the teams' three-game series at Busch Stadium.

"I learn everything I can from him," St. Louis first baseman Jose Martinez said of Molina. "I sit next to him in every situation and try to absorb what he says. He knows how to take advantage of every situation."

Take Tuesday night's rout, for instance. With the bases loaded in the first inning and two outs, Molina didn't try to do too much with Robert Stephenson's 3-2 changeup that floated to the plate's inner half, just above the belt. He ripped a two-run double to put the Cardinals ahead for good.

After walking and scoring in the third, Molina made his last at-bat count in the sixth. With first baseman Joey Votto playing off the line, Molina poked an RBI hit down the right-field line before taking off the last three innings, replaced by Carson Kelly.

Seven other hitters knocked in runs as St. Louis (76-68) stayed within two games of the Chicago Cubs for first place in the National League Central. The Cardinals also remained 3 1/2 games behind Colorado for the NL's second wild-card spot.

On Wednesday, Jack Flaherty (0-0, 6.00 ERA) will draw the start for the Cardinals opposite Tyler Mahle (0-2, 3.60 ERA) in a matchup of rookies called up in recent weeks.

Flaherty last pitched Sept. 6 in San Diego, getting a no-decision after allowing one run on three hits in five innings. He walked four and fanned four in a game St. Louis went on to win 3-1.

This will be Flaherty's first career start against Cincinnati (62-83), and he will have to deal with the best lineup he has seen so far after facing the San Francisco Giants and the Padres. The Reds can boast six 20-homer hitters after shortstop Zack Cozart reached the milestone for the first time in his career with a 433-foot blast in the first inning Tuesday night.

One of those 20-homer guys, second baseman Scooter Gennett, may miss the Wednesday game. Gennett departed before the bottom of the fifth inning Tuesday night due to left hand inflammation.

"I think he pulled a ball foul and the webbing between the thumb and his index finger really got inflamed," Cincinnati manager Bryan Price said Tuesday, "so we'll see where he's at tomorrow."

Mahle last worked Thursday night, dropping a 7-2 decision to the New York Mets. He lasted just four innings, allowing three runs on six hits and four walks while striking out two.

It will be his first career start against St. Louis, which is 9-2 in September and has won 11 of 14 games to charge into contention.