The Houston Astros' rookie left-hander seeks his third straight scoreless outing in a bid to snap the Rangers' seven-game win streak in Monday's series finale.
Rios was brought over in a waiver deal from the Chicago White Sox on Friday and has gone 4 for 7 with two extra-base hits and two RBIs in his first two games with Texas (68-50). That's helped the Rangers win 12 of 13 and surge one game ahead of Oakland in the division.
Texas has welcomed Rios' instant impact after losing slugger Nelson Cruz to a 50-game drug suspension last Monday.
While trying to maintain their lead, the Rangers will seek to match their season-high, eight-game win streak from April 12-21, 2012. They haven't won eight in a row on the road in a single season since June 12-20, 2010, and have never swept a four-game series over the Astros (37-79).
"Ride the wave," second baseman Ian Kinsler told the team's website. "Just play hard every day and come to win. That's it. ... The confidence level everyone on the club, we all understand it's not one person, it's a collective group. It seems like we have a chance to score every inning. That's comforting."
Houston is seeking to avoid its first six-game home losing streak since dropping eight straight Aug. 12-31, 2012.
"We've been in position to win ballgames, but this is major league baseball," manager Bo Porter said. "Nobody is walking away feeling like it's a moral victory. I don't believe in moral victories, in the first place."
Oberholtzer (2-0, 2.53 ERA) will try to boost his club while extending a 16-inning scoreless streak and earning his third win in as many major league starts.
The left-hander is the first Astros player with at least 14 scoreless innings in his first two starts and the first major leaguer to toss seven or more scoreless frames in his first two since Philadelphia's Marty Bystrom in 1980.
Oberholtzer gave up four hits and two walks in his most recent outing, a 2-0 win over Boston last Monday.
"For me, my mindset is just to attack and throw strikes. I'm always confident," he said.
While he might have some confidence, Oberholtzer is facing a team that's won 14 of 16 over the Astros and 18 of 21 at Minute Maid Park, including a series-best eight in a row there.
Yu Darvish (11-5, 2.72) will try to deliver that victory by earning his third straight win and fourth in five starts. He's 3-1 with a 1.37 ERA in his last four outings but wasn't at his sharpest in an 8-3 victory at the Los Angeles Angels on Tuesday.
He gave up two home runs in one inning in the first time in his career and allowed three runs over seven innings.
"It was probably the worst outing I've had this year," he told the team's website. "But I was able to keep the game close and contribute to the win."
Darvish was 3-0 with a 1.90 ERA in his first three starts against Houston, including two at Minute Maid this season, but gave up five runs over six innings in losing 9-5 in the most recent matchup on July 6.