The Dodgers, who have won seven straight over the defending World Series champions, will try to extend that run Monday night when they open a four-game series in St. Louis.
Los Angeles lost two of three to both San Diego and Philadelphia to start the second half of the season, but regrouped with a three-game sweep of the New York Mets at Citi Field over the weekend.
The Dodgers (52-44) won 8-3 in 12 innings Sunday for their fourth straight win. After blowing a 3-1 lead in the sixth, Matt Treanor's two-run single triggered a five-run 12th.
Los Angeles, which dropped 19 of 25 before its current winning streak, has totaled 28 runs in the four wins after scoring 19 the previous six.
"I think we're getting back into that type of, 'We can do this' mood," Treanor said.
Matt Kemp's return has helped. He had two hits and scored twice Sunday, and is hitting .378 with two homers, six RBIs and six runs scored in eight games since missing six weeks with a strained left hamstring.
Kemp sat out the Dodgers' series against the Cardinals in May, although it didn't matter as Los Angeles swept the three-game set.
While Los Angeles is 1 1/2 games behind San Francisco in the NL West and one-half game out of the two wild-card spots, St. Louis (50-45) is chasing Cincinnati and Pittsburgh in the Central. The Cardinals are five games back of the Reds and two behind the wild-card leaders.
St. Louis lost five of six coming out of the All-Star break but swept Chicago at home over the weekend, winning the final two 12-0 and 7-0.
Beltran's home run was his 21st and first since June 24. He's 5 for 15 in his last four games after batting .163 over the previous 12 with one extra-base hit.
"It's just a matter of kind of putting it together and those hits falling in timely spots," manager Mike Matheny said. "That was probably one of the more frustrating things with the trip we just had. Hopefully we can ride this out for a while."
The Cardinals will try to extend their winning streak as they face Chad Billingsley (4-9, 4.30 ERA), who is scheduled to come off the disabled list and trying to avoid losing a career-worst sixth consecutive start.
The right-hander gave up four runs in six innings of a 5-3 loss to Arizona on July 7. The Dodgers then placed him on the disabled list, retroactive to July 8, with right elbow inflammation.
"We were just being cautious and we didn't feel like we could send him out there without getting his elbow looked at," manager Don Mattingly said.
Billingsley has a 6.21 ERA while opponents are hitting .345 off him during his skid.
He is 1-3 with a 4.63 ERA in his career versus the Cardinals, including 0-2 with a 6.41 ERA in four starts in St. Louis. Billingsley has allowed 13 runs over 9 2-3 innings in his last two starts there.
Holliday is 8 for 25 with three homers against Billingsley, who gave up five runs in six innings of a 6-5 win over St. Louis on May 20. He didn't factor in the decision.
After back-to-back shutouts of the Cubs, rookie Joe Kelly (1-2, 2.75) will try to extend St. Louis' 25-inning shutout streak.
Kelly gave up three runs in six innings of a 3-2 loss to Milwaukee on Tuesday. The Cardinals have scored three or fewer runs in five of the right-hander's seven starts.