Texas Rangers starter Nick Tepesch had solid performances in his previous three starts, winning the last two.
Saturday against the suddenly slugging Washington Nationals he was done after the second inning.
Anthony Rendon went 4 for 5 and hit one of four Washington home runs, including two off the Texas starter, as the Nationals routed the Rangers 10-2.
Jose Lobaton also connected off Tepesch (2-1), who allowed five runs on seven hits.
"I think what caused him his demise (was) early on he was going deep in counts, and that's a fastball hitting team, and he had to try and throw a strike," manager Ron Washington said. "And when he did they made him pay for it."
The 25-year-old right-hander, who walked two and struck out one, saw his ERA jump from 2.95 to 4.43.
"Didn't really help myself out is the best way to put it," Tepesch said. "Falling behind, and you're not going to win games falling behind and letting pitches leak back over the middle."
Washington starter Doug Fister (3-1) came in with a 5.67 career ERA against the Rangers, but didn't give up a hit until Elvis Andrus doubled in the fourth. He allowed two runs and retired the first 10 Texas batters.
"He goes out and executes his game plan and throws all his pitches for strikes, works fast, and did the same thing today," Mitch Moreland said.
The Rangers lost their second straight and fell to 6-4 on their 11-game road swing and Washington was asked if the trip is beginning to take its toll.
"No, I think (Friday Washington starter Stephen) Strasburg and Fister did," he said. "You know when pitching shuts you down you look like you might be a little fatigued, but if we could have put something together and had a chance to run the bases and make something happen it wouldn't have looked so lethargic."
Adam LaRoche and Scott Hairston homered off Scott Baker, who pitched five innings in relief, sparing the Rangers bullpen.
"He certainly gave us what we needed," Washington said.
The Nationals have racked up 24 runs and 42 hits in their last three games, winning two straight to climb back to .500.
Rendon had six straight hits over two games before striking out in the eighth.
The Nationals took a 1-0 lead in the first when Rendon lined Tepesch's pitch into the Rangers' bullpen for his sixth home run.
In the second, Lobaton, spelling Wilson Ramos in a day game after a night game, worked the count to 3-2 before hitting a two-run homer to right center.
Tepesch had given up just two homers in 18 1-3 innings before Saturday.
The Nationals weren't done in the second, with singles by Denard Span and Rendon. Jayson
Werth doubled and the ball was bobbled in left by Shin-Soo Choo. Both Span and Rendon scored to make it 5-0.
Texas wasn't charged with any errors in the fourth inning, but two plays they didn't make allowed Washington to break the game open.
Andrus lost Fister's pop-up in the sun and it fell for a lead-off single. Then with first and second and one out, Werth hit a smash that Andrus bobbled before recovering to get the force at second, with Werth just beating the relay.
LaRoche then followed with a 3-run shot, putting the Nationals up 8-0.
The Rangers got to Fister in the fifth when Alex Rios walked and scored on a double by Rougned Odor, and Moreland added an RBI single in the sixth.
Hairston, pinch-hitting for Werth, hit a two-run homer in the sixth.