The Rockies also seek back-to-back wins for the first time in more than three weeks Thursday while forcing a split of their four-game series against the Atlanta Braves.
Colorado (30-35) has lost 13 of 16 but its hitters have tried to do their part of late. The Rockies are batting .296 and have scored 42 runs in their last eight contests, but are 2-6 in that stretch, which has come with Carlos Gonzalez, Michael Cuddyer and Nolan Arenado on the disabled list.
They've produced 13 hits in each of the past two games in this series but lost 13-10 on Tuesday. Colorado won 8-2 on Wednesday with Corey Dickerson driving in three runs.
The Rockies have provided 5.46 runs per game for their starters - among the most in the majors - but Chacin has been backed with only 2.33 per game in his seven starts this season. He's gotten three runs in each of the last two games and hasn't received a decision in both.
Chacin (0-4, 5.35 ERA) pitched six scoreless innings Saturday against the Los Angeles Dodgers before getting charged with three runs in the seventh in a 5-4 victory in 10 innings.
"Jhoulys looked like himself again today," manager Walt Weiss said. "That's what we're used to seeing, and it's a great sign for him and us. ... I wish he would have gotten a (win) there."
Chacin is 0-2 with a 6.23 ERA in three career starts against the Braves and is facing them for the first time since a 1-0 loss at Turner Field on Sept. 6, 2012.
Ervin Santana (5-2, 3.69) will try to keep Chacin from earning his first win since Sept. 20 while helping the Braves (34-30) finish 3-1 in their lone visit to Coors Field. Atlanta is also seeking to move back into a tie for the NL East lead after falling one game behind Washington on Wednesday.
Santana is coming off his best outing in nearly a month but did not get enough support to win a second straight start. The right-hander gave up one unearned run over seven innings Saturday in Arizona, but the Braves lost 4-3 in 11 innings.
Santana was 1-2 with a 7.83 ERA in his previous four outings.
He's 2-0 with a 5.59 ERA in three career starts against Colorado. Santana was charged with seven runs in 5 2-3 innings in his most recent matchup and only game at Coors Field, a 10-8 win for the Los Angeles Angels on June 10, 2012.
Evan Gattis might get to help his potential battery mate by extending his hit streak to 13 games. Gattis, who has never faced Chacin, is batting .383 (18 for 47) with five homers and 13 RBIs during his run.
"He's good. He's awesome. He's so strong. His approach is getting better and better," third baseman Chris Johnson told the team's website.
Freddie Freeman is 3 for 6 with a pair of solo homers in his career versus the Colorado right-hander while Justin Upton is 1 for 16 with 10 strikeouts.