AP Sports Writer
PHOENIX (AP) -- Patrick Corbin walked off the mound for the final time this season, his head down in disappointment.
"But I told him to keep his head up," manager Kirk Gibson said. "He had an outstanding year for us."
The last half-season, though, was not so good, culminating with Friday night's 8-4 loss to the Washington Nationals.
After opening the season 12-1, Corbin finished 2-7.
"This last month has been difficult for me and something I want to get over," he said. "The team didn't like how the season ended, but at the end of the year when I get back home I will try to improve and get better and make sure it doesn't happen again next year."
Corbin gave up 32 runs in his last 34 innings. Gibson said the young left-hander's slider, so devastating early in the year, was not as good as the season wore on.
"He is a very determined young man who doesn't like to lose, doesn't like to fail," Gibson said. "He didn't run from it, he didn't want to get shut down. He was honest with us. He said he felt fine physically. It was obvious that he wore down, that he didn't have the same stuff."
On the other hand, Washington's Stephen Strasburg had a strong finish to his season, with the help of three-run homers from Jayson Werth and Wilson Ramos.
Strasburg (8-9) gave up two runs and six hits in seven innings with four strikeouts, two walks and a hit batter.
Manager Davey Johnson, who is retiring at the end of the season, said Strasburg's win-loss record in no way reflects the way he pitched.
"He had a great season. He's a phenomenal young man, going to have a great career," Johnson said. "We didn't score him any runs. He should have won 15 ball games, at least. Certainly he was consistent all year long. "
Strasburg, whose season is littered with no decisions, had a solid finish after being shut down in the late stages of last season to rest his arm even though Washington was on a playoff run.
He was 3-0 in his last eight starts. The Nationals won seven of them.
"I think physically I held up pretty well," Strasburg said. "I think one thing I learned is sometimes less is more. I like to work really hard and when you reach a point in September you've really got to back things off or it's going to be counterproductive."
The Diamondbacks lost their third straight to fall to 80-80 for the season. They have not been under .500 all year.
"This is frustrating, the last couple of games and how it is gone," Arizona outfielder A.J. Pollock said. "You really want to roll into the offseason with some momentum and something to look back on and build from. For me personally that is what I am trying to do. I am trying not to limp to the finish line."
Arizona broke a scoreless tie in the third when Didi Gregorius drew a leadoff walk and Corbin was hit in the foot by a pitch. Adam Eaton's single loaded the bases, then Gerardo Parra singled home the game's first run. Paul Goldchmidt grounded sharply into a double play, but a run scored to make it 2-0.
Washington got a run in the fourth on Bryce Harper's RBI double, then took over with a four-run fourth.
Consecutive doubles by Tyler Moore and Anthony Rendon tied it at 2-2. Jeff Kobernus walked and, with two outs, just after he had broken a bat he had used for weeks, Werth hit one long and hard off the pitch-count scoreboard just below the Friday's Front Row Sports Grill in left field. The three-run shot put Washington in control 5-2.
Ramos blew the game open with his three-run shot in the eighth.
Down 8-2, the Diamondbacks scored twice in the ninth on Gregorius' groundout to short and Matt Davidson's double to center.
Goldschmidt singled in the fifth to extend his hitting streak to 17 games, matching his career best set earlier this year.
NOTES: Strasburg threw 183 innings this season, Corbin 208 1-3. Strasburg is 25, Corbin 26. ... Johnson says LHP Gio Gonzalez could start the season finale Sunday but indicated the situation remains in flux. ... The run that scored when Goldschmidt hit into a double play does not count toward his NL-leading total of 124 RBIs. Goldschmidt leads the NL with 36 HRs, one more than Pittsburgh's Pedro Alvarez. ... Washington has four players with at least 20 HRs: Ryan Zimmerman (26), Werth (25), Harper (20) and Ian Desmond (20). ... Arizona dropped to .500 (80-80). The Diamondbacks have not been under .500 all season. Last year they finished 81-81. ... On Saturday night, Washington sends RHP Dan Haren (9-14, 4.87) to the mound against Arizona's RHP Brandon McCarthy (5-10. 4.64).
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