The Cardinals are in second place in the National League Central, a half-game back of the Chicago Cubs. They currently hold the second wild-card slot, 1 1/2 games up on the New York Mets and Philadelphia Phillies.
The Rockies sit in last place in the NL West and well outside of the wild card race. They have played better lately, however, winning five of their last seven games.
"It's so much easier when you have success to be in a good mood and talk about the right things," Rockies second baseman Ryan McMahon told MLB.com during this recent upturn. "Throughout this season, we haven't been there the whole time. But we're there right now. Hopefully, we'll keep it rolling."
Overall, though, the Rockies are 14-30 since June 30 and they have suffered multiple pitching casualties.
The Rockies ace starting pitcher Jon Gray was placed on the injured list on Wednesday with a season-ending left foot fracture, joining reliever Scott Oberg (blood clot in his pitching arm). Starting pitcher Kyle Freeland left his start Tuesday with a left groin strain.
The Rockies are facing the Cardinals for the first time this season. They will send their top remaining starter, German Marquez (12-5, 4.71 ERA), to the mound for the series opener.
He is 2-0 with a 1.53 ERA in three career starts against the Cardinals.
Marquez has beat the Miami Marlins and San Diego Padres in his last two starts. He allowed five runs on 10 hits (including three homers) in 13 innings in those victories while striking out 17 and walking just three.
He is 4-0 in his last six starts with a 3.32 ERA and 43 strikeouts and just five walks.
The Cardinals, who have won nine of their last 12 games, will counter with Miles Mikolas (7-13, 4.30). He struggled in his last two starts, allowing 11 runs (10 earned) on 14 hits, including four homers, in 10 innings.
But he has walked two or fewer batters in 40 consecutive starts, a team record. And Mikolas has been much better at home (5-5 with a 2.43 ERA in 12 starts) than on the road (2-8, 6.54 in 13 starts) this season.
In four career appearances against Colorado, including two starts, Mikolas has no decisions and a 5.40 ERA.
Cardinals manager Mike Shildt has tried some new looks with his lineup with outfielders Jose Martinez (shoulder) and Tyler O'Neill) sidelined by short-term injuries.
He plugged Harrison Bader back into center field upon his return from Triple-A Memphis and he moved hot-hitting Kolten Wong up to the No. 2 slot in the batting order in Wednesday night's 5-3 loss to the Milwaukee Brewers.
Wong has hit .355 since the All-Star break after hitting just .244 before it.
"Obviously it's cool to hit at the top of the lineup, get more (at-bats), get into more situations where I can help the team win," Wong told reporters. "When you're at the bottom, you're in situations where you're just trying to get on base and hopefully something happens. But hitting second is going to be fun because I'm in the thick of things."
--Field Level Media