PHOENIX (AP) - Jeff Karstens looked good for a pitcher fighting fatigue problems, keeping hitters off balance with a knee-buckling curve.
He just wasn't good enough to beat Ian Kennedy, thanks to a broken-bat homer by Justin Upton.
Karstens bounced back from an average return to the rotation to throw six effective innings, but was outpitched by Arizona's Cy Young Award candidate in the Pittsburgh Pirates' 1-0 loss to the NL West-leading Diamondbacks on Monday night.
``Jeff was very, very good today, but unfortunately for us their guy was one run better,' Pirates manager Clint Hurdle said.
Karstens (9-9) missed two starts in September due to shoulder fatigue, thanks in part to a career-high 156 1-3 innings, and was just OK in his return last Tuesday against St. Louis.
But the right-hander was sharp against the Diamondbacks, scattering four hits over the first five innings before Upton hit his bizarre homer.
Upton's bat flew to the dirt at third base and he was left with only the handle in his hands as the ball sailed just out of the reach of Alex Presley in left. A fan got a piece of the ball as he reached out over the wall and Hurdle ran out to ask if there was interference, but the homer was upheld after a quick video review by the umpires.
Karstens was lifted for a pinch-hitter after allowing five hits and a run in six innings.
``I wanted to go back out,' he said. ``It was a 1-0 ballgame. I felt like I still had good stuff.'
Just not as good as Kennedy's.
Arizona's ace had the Pirates guessing all night, giving up one hit - to Karstens, no less - while matching his career high with 12 strikeouts to become the fourth Diamondbacks pitcher to reach 20 wins.
Kennedy (20-4) seemed to get stronger as the game went on, striking out the final six batters he faced. J.J. Putz closed out the two-hitter and his 42nd save by stranding Presley to trim Arizona's magic number to four over idle San Francisco.
``Our guys were trying to stay after it all night against him,' Hurdle said. ``He was very, very sharp.'
The Diamondbacks were firmly in control of the NL West just a couple of weeks ago, leading by 9 1/2 games with 16 left. They entered the three-game series against Pittsburgh a little more white knuckled thanks to San Francisco's eight-game winning streak and a three-game skid of their own that ended with a win over San Diego on Sunday.
Arizona hoped to climb closer to its first division crown since 2007 against the fast-fading Pirates, who led the NL Central in late July but fell 22 games out of first after a 15-1 loss to the Dodgers on Sunday.
The Diamondbacks figured to have a good shot with Kennedy on the mound.
Arizona's ace has become a legitimate Cy Young Award contender by allowing one run or less 16 times on his way to a 2.88 ERA. The right-hander had gone 11-1 with a 2.42 ERA in his previous 13 starts and had a 1.69 ERA while winning his previous six outings at Chase Field.
Kennedy overmatched the Pirates from the start, retiring the first eight hitters before Karstens, an .087 hitter, lined a single through the left side. Kennedy was sharp after that, leaving after eight innings and 113 pitches to join Randy Johnson and Curt Schilling (2001-02) and Brandon Webb (2008) as the only 20-game winners in Diamondbacks history.
``This is the most important part, which is winning games, taking away that magic number and clinching here pretty soon,' said Kennedy, who joined Detroit's Justin Verlander as the only 20-game winners in the majors.
NOTES: Arizona RHP Daniel Hudson will pitch the second game of the series after having his four-game winning streak snapped by the Dodgers in his last outing. He's tied for fifth in the NL with 16 wins. ... RHP Charlie Morton, who will start for Pittsburgh on Tuesday, has lost four straight decisions since his last win on Aug. 8 at San Francisco. It will be his sixth attempt at winning his career-best 10th game.
Copyright 2016 by STATS LLC and Associated Press.
Any commercial use or distribution without the express written
consent of STATS LLC and Associated Press is strictly prohibited.