Cardinals New-Look Lineup vs. Reds: Joshua Báez Leads Off, JJ Wetherholt Out

The St. Louis Cardinals have a big day ahead against the Cincinnati Reds on Monday.

Aug 15, 2026; Chicago, Illinois, USA; St. Louis Cardinals left fielder Joshua Baez (22) celebrates as he rounds the bases after hitting a two-run home run against the Chicago Cubs during the first inning at Wrigley Field. Mandatory Credit: Kamil Krzaczynski-Imagn Images | IMAGN IMAGES via Reuters Connect

The St. Louis Cardinals have a big day ahead on Monday with doubleheader scheduled against the National League Central rival Cincinnati Reds.

Game 1 of the day-night doubleheader is scheduled to kick off with the first pitch at 12:40 p.m. CDT. Game 2 is scheduled to begin at 5:40 p.m. CDT.

When the action kicks off on Monday, the most interesting thing to watch out for is going to be the performance of young lefty Quinn Mathews. He's returning to the big leagues to make his second career MLB start. His first came on Aug. 1 against the Toronto Blue Jays. Monday will be another opportunity for him to show the Cardinals' front office that he belongs in the majors from here on out.

But that's not all, the Cardinals released a new-look lineup for Game 1. The Reds are promoting lefty Kent Emanuel to make his first big league appearance since 2024. So far this season, he has only pitched one game in the Reds' organization. That was a start in Triple-A on Aug. 9. Before that, he was pitching in Indy Ball. He's going to have a significant test right away with Cardinals slugger Joshua Báez set to lead off and JJ Wetherholt having the day off.

Cardinals Lineup Vs. Reds for Game 1 on Monday

Aug 15, 2026; Chicago, Illinois, USA; St. Louis Cardinals left fielder Joshua Baez (22) celebrates after a baseball game against the Chicago Cubs at Wrigley Field. Mandatory Credit: Kamil Krzaczynski-Imagn Images TPX IMAGES OF THE DAY | IMAGN IMAGES via Reuters Connect

1. Joshua Báez, LF
2. Iván Herrera, DH
3. Jordan Walker, RF
4. Alec Burleson, 1B
5. José Fermín, 2B
6. Masyn Winn, SS
7. Blaze Jordan, 3B
8. Everson Pereira, CF
9. Pedro Pagés, C

Playing two in Cincy pic.twitter.com/KPEz9twmSI

— St. Louis Cardinals (@Cardinals) August 17, 2026

Báez made his big league debut over the weekend and caught the attention of the big league world in general. The young slugger became the first player in Major League Baseball history to crush three home runs in an MLB debut. He batted fifth on Saturday and Sunday. Now, just a few days later, the Cardinals are trusting him at the top of the lineup against a lefty who surely will have some nerves as he returns to the majors for the first time since 2024.

The Cardinals aren't messing around either with three righties at the top of the order.

Wetherholt is out of the lineup, but there's nothing to worry about at this time. He has played in 118 of 124 games for the Cardinals so far. He's alright, just rest.

Again, the most intriguing thing about this lineup is Báez at the top. St. Louis waited months to give him a shot, but clearly it thinks very highly of the young slugger.