WASHINGTON (AP) -- The San Diego Padres say the only way they'll break this skid is to keep battling. Count catcher Yasmani Grandal as one of the casualties.
The Washington Nationals rallied for two runs in the seventh inning and a 5-4 victory Saturday, sending the Padres to their eighth straight loss on their 10-game road trip.
That negated another solid outing from starter Jason Marquis and a three-run, go-ahead home run by Jesus Guzman that made it 4-3 in the top of the sixth.
Guzman also hit one of three Padres doubles in the first three innings, but they went only 1 for 14 with runners in scoring position, including 0 for 9 against Nationals starter Jordan Zimmermann, who lasted just 5 1-3 innings.
"I tell you, this game is weird," said Guzman, who is 7 for 11 with three doubles and a home run in his last three games. "I've had three or four home runs to give us the lead, and we've lost. And we win the game (recently) at home when I get hit by pitch."
To add injury to insult, the Padres appear to have lost Grandal for at least two weeks with a right knee injury after Washington's Anthony Rendon slid into him on a forceout in the third inning.
"It looks as though there is some damage to the ACL and MCL," manager Bud Black said of Grandal, who served a 50-game suspension to begin the season after testing positive for a banned substance. "In a couple minutes the pain subsided, but I think he knew something was wrong."
Black said Grandal would be placed on the disabled list and that catcher Rene Rivera would be called up from Triple-A Tuscon. Grandal said he'll have an MRI exam Monday in San Diego.
Bryce Harper, who talked his way into the lineup after manager Davey Johnson said Friday night he'd probably give the struggling left fielder the weekend off, drove in three runs for the Nationals, including a game-tying sacrifice fly off reliever Joe Thatcher.
Ryan Zimmerman knocked in the go-ahead run off Luke Gregerson, who entered after Harper's sacrifice fly. After striking out Roger Bernadina to begin the seventh, Nick Vincent (2-1) allowed singles to Denard Span and Ian Desmond before he was lifted for Thatcher.
"We've been playing better lately and obviously scoring runs later in the game and getting hits like that, so (we've) got to keep doing that and take it one game at a time slowly just kind of creep up," Zimmerman said of the Nationals, who have won three straight.
Ross Ohlendorf (2-0) got the win and Rafael Soriano pitched the ninth for his 24th save. Soriano allowed a pair of singles with one out, but retired pinch hitter Mark Kotsay and Everth Cabrera -- on a diving stop by LaRoche at first -- to end it.
Marquis went six innings, allowing three runs on eight hits. He struck out three, walked three and also contributed at the plate with a double and an RBI groundout.
It was his sixth quality start in his last seven outings. Marquis is 3-2 with two no-decisions in that stretch.
San Diego (40-48) entered Saturday just 5 1/2 games out of the NL West lead.
"It's not fun," Marquis said. "Fortunately we're in the right division right now where we're not too far out. Hopefully we can get this turned around and get back in the win column, and go home where we've been playing some good baseball."
Trailing 3-1 in the sixth, the Padres got one-out singles from Carlos Quentin and Chase Headley.
Johnson lifted Zimmermann after he had thrown 101 pitches and brought in Ohlendorf to face Guzman, who deposited a 1-1 fastball in the Padres' bullpen to give San Diego the lead.
Washington took the lead in the third. Rendon led off with a single and Kurt Suzuki doubled him to third. Zimmermann struck out, but Span walked to load the bases. Desmond grounded into a fielder's choice, with Rendon clattering into Grandal at home, but Harper walked to make it 1-0.
Adam LaRoche made it 2-0 when he led off the fourth with his 13th homer of the season, a line drive into the Nationals' bullpen.
"That was a wild game," Johnson said. "We had chances to put Marquis out of his misery early and couldn't do it, but kept battling."
San Diego got a run back in the fifth when Logan Forsythe walked and later scored on Marquis' grounder to short.
Washington got it right back when Span singled, stole second, went to third on a bloop single by Desmond and scored on Harper's single.
NOTES: Black said 2B Jedd Gyorko (groin) did some running before Saturday's game and hopes to play a minor league rehab game in the middle of next week. . San Diego LHP Robbie Erlin (1-1, 4.34 ERA) opposes Stephen Strasburg (4-6, 2.24) in Sunday's series finale.
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