It was exactly the type of start manager Ron Washington had hoped he would get from his club in the opener of this critical three-game series against the first-place Athletics.
Murphy hit two of the Rangers' season-high four home runs to back an uneven start by Lewis, and Texas beat Oakland 14-8 on Monday night.
"We needed everything we put on the board," Washington said after the Rangers pounded out 16 hits and matched their season high for runs. "They kept fighting back but we didn't stop playing. Tonight it took 14, and we were able to get it."
Michael Choice and Robinson Chirinos also homered, and Adrian Beltre drove in three runs to lead the Rangers to their fourth straight win at the Coliseum. Texas swept a three-game series in Oakland in April.
The Rangers, who began the night eight games behind the division-leading A's, nearly let the game slip away. They led 11-3 before Oakland scored four times in the sixth and once in the eighth.
Murphy, who hit a two-run homer in the fourth, helped seal the victory with a solo shot in the ninth for his fourth career multihomer game.
"I'd be lying to you if I said I didn't get a little bit nervous right there when it got 11-8," Murphy said. "The game could have easily slipped away ... (but) we put together some good at-bats and got a few more runs and felt a little more comfortable again."
Lewis (5-4) allowed 10 hits and five runs over 5 1/3 innings to win for the first time since May 25. The one-time A's farmhand, pitching on five days' rest, worked in and out of trouble most of the night off the same mound he made his final appearance on in 2012 before missing nearly two full seasons due to a series of injuries. Lewis struck out two and walked three.
"Up until the sixth inning, he had only given up three runs, so he was pitching pretty good," Washington said. "Then his velocity came down a little bit and he just couldn't hit his spots anymore so I had to go get him."
Texas tied it on Chirinos' two-run single off Oakland starter Drew Pomeranz in the second, then broke the game open with a six-run fourth. Murphy hit a two-run home run, Robertson added an RBI single and Rougned Odor scored on a fielder's choice to chase Pomeranz.
Beltre's two-run double off reliever Ryan Cook made it 8-2. Beltre added a sacrifice fly in the sixth.
"For a team that leads the league in pitching and usually holds clubs to under four, we haven't been able to do that (lately)," Oakland manager Bob Melvin said.
Lewis and five Texas relievers made the lead hold up.
The A's, who scored twice in the first, pulled to 10-3 on Moss' towering solo home run in the fifth.
Lewis left after giving up back-to-back doubles to Alberto Callaspo and Crisp in the sixth. Pinch hitter Kyle Blanks drew a walk off reliever Robbie Ross Jr. before Cespedes hit his 13th home run to cut the gap to 11-7.
Murphy and Chirinos hit back-to-back home runs off Fernando Abad in the ninth.
Pomeranz (5-4) struggled in his shortest outing since joining the A's rotation in early May. He allowed eight hits and eight runs -- seven earned -- with two walks and four strikeouts.
"I got into some bad counts," Pomeranz said. "Once that happens, you become predictable. They waited for mistakes and jumped on them."
Callaspo had four hits for Oakland in his first game since being reinstated from the paternity list.
A's starters had not allowed a home run in seven games before giving up four to Texas. ... A moment of silence was held before the game for Hall of Fame OF Tony Gwynn, who died earlier in the day. ... The A's activated INF Jake Elmore from the 60-day DL and optioned him to Triple-A Sacramento. ... Oakland agreed to terms with 3B Matt Chapman, its first-round pick, and SS Trace Loehr, a sixth-rounder. ... RHP Yu Darvish (7-2) pitches for Texas on Wednesday, seeking to extend his career-best four-game winning streak. He'll oppose Oakland LHP Tommy Milone (4-3).