So the way he concluded a disappointing season in a 2-0 victory over Arizona on Saturday night brought a mixture of satisfaction and sadness.
He felt satisfaction that at least he had pitched well lately, disappointment that his year or the Nationals' season wasn't what they had envisioned.
"I can't believe that it's over," Haren said. "It seems like yesterday I was flying to D.C. and getting a tour of the facility with Riz (general manager Mike Rizzo) and here we are 10 months later and I'll probably take off the Nats uniform for the last time tomorrow. It happened fast. Things go quick, and it's sad a little bit."
Haren (10-14), the former Diamondbacks pitcher who signed a one-year, $13 million deal with the Nationals and struggled mightily for much of the season, allowed four hits in seven innings. He struck out five and walked one.
The 33-year-old right-hander, a free agent at the end of the season, was 6-2 in his last 12 starts.
When the game was over, manager Davey Johnson gathered the team together and thanked them.
Johnson, 70, is retiring after three decades as a player, then manager. There was applause and hugs, and the players gave Johnson a bottle of wine.
Johnson had come up with a motivator for this final series after Washington was eliminated from playoff contention Monday in St. Louis.
He wanted to end his career with at least 300 more wins than losses. Saturday night's victory made sure that would happen.
"It's wonderful," Johnson said. "The effort was outstanding. I can't even put words on it. Tomorrow I'm going to play the young guys. Some of the other guys, their seasons are finished. They battled hard. I really thanked them a lot for the effort and I know they're in a good place going forward."
Brandon McCarthy (5-11) gave up two runs and five hits in seven innings.
With the loss, Arizona fell to 80-81, the first time the Diamondbacks have been under .500 this season.
"We just haven't hit,' manager Kirk Gibson said . "We scored 11 runs in six games. He (Haren) pitched a good game and we give him credit, but you have to have better opportunities and make the most of your opportunities.
"We had it at the end, but we couldn't get it down. You throw seven innings and give up two runs you expect to win those games."
Drew Storen threw a scoreless eighth as the third link of the shutout.
Span tripled to the right-field corner leading off the sixth and scored when Ryan Zimmerman grounded out.
In the seventh, Tracy hit a solo shot that landed on the far side of the swimming pool in right field and bounced back into the water.
Meanwhile, Arizona didn't do much against Haren, with all four of its hits coming with two outs.
McCarthy had a solid final outing in an injury-filled season but got no offensive support from the Diamondbacks, who lost their fourth straight.
The right-hander retired the first 11 batters before Jayson Werth singled.
The game whizzed by in 2 hours, 25 minutes.
After the game, Johnson said he had scratched RHP Gio Gonzalez from Sunday's start and would go with Tanner Roark (7-1, 1.74). LHP Wade Miley (10-10, 3.63) goes for Arizona. ... Goldschmidt extended his career-best hitting streak to 18 games. Goldschmidt fell into a tie for the NL lead in homers when Pedro Alvarez of Pittsburgh hit his 36th on Saturday.
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