PITTSBURGH (AP) -- Jason Grilli put himself in a tough situation and couldn't get out of it.
Behind in the count 2-0 with the score tied in the ninth inning, the Pittsburgh closer had no choice but to throw Todd Frazier a fastball.
Frazier was looking for it and hit a leadoff home run to center field Tuesday night, sending the Cincinnati Reds to a 6-5 victory over Grilli (0-2) and the Pirates.
"You can't fall behind the first guy you face, especially in a tie ballgame," Grilli said. "He dives over the plate. ... It just didn't work out."
Frazier's home run was his team-high 16th and it gave the Reds their fifth win in six games. The Pirates lost their second straight after winning four in a row.
Frazier leads NL third basemen in homers, extra-base hits (31) and slugging percentage (.524).
"I know he didn't want to walk me and put a guy on base," Frazier said. "I was looking to get a fastball I could handle and, fortunately, I was able to connect."
The Pirates used a three-run seventh to tie the score at 5 on RBI singles by Ike Davis, Russell Martin and Josh Harrison.
"We got nicked early but we came back with three," Pittsburgh manager Clint Hurdle said. "We've just got to be a little more efficient and get a one-run game like this to come our way."
Logan Ondrusek (2-2) got four outs for the win. Aroldis Chapman pitched a scoreless ninth for his 12th save, getting Clint Barmes to fly out to the left-field fence with two runners on to end the game.
"I've seen so many ballgames here, but I'm still never sure if a ball is going to carry out to left field," Hurdle said. "I thought it had a chance. Unfortunately, it was a few inches short."
Harrison matched a career high with four hits. He drove in two runs.
Starling Marte, Davis and Jordy Mercer added two hits apiece.
Andrew McCutchen extended his hitting streak to 12 games but came up short of becoming the first Pittsburgh player to have multiple hits in nine straight games since Rennie Stennett in 1971. Gregory Polanco became the first Pirates player to have a hit in each of the first seven games of his career since Hall of Famer Roberto Clemente in 1955.
Billy Hamilton had three hits and two stolen bases for the Reds, while Joey Votto had two hits and three RBIs. Frazier, Brandon Phillips and Ryan Ludwick added two hits apiece.
Hamilton is 8 for 13 in his last three games. Cincinnati is 5-2 and averaging 5.3 runs per game since Votto was activated from the disabled list after missing three weeks with a quadriceps strain.
Pittsburgh rookie Brandon Cumpton gave up three runs and eight hits in six innings after winning his previous two starts.
Cincinnati starter Johnny Cueto's hard luck continued as he gave up two runs in six innings of a no-decision. Cueto scattered seven hits and four walks, but the bullpen failed to hold a three-run lead for him. Despite a sparkling 1.92 ERA, Cueto is 6-5 through 15 starts.
In two starts against the Pirates in April, he allowed one run and six hits in 18 innings.
NOTES: Pittsburgh 2B Neil Walker took batting practice and fielded grounders before the game for the first time since undergoing an appendectomy June 9. He is optimistic he will be ready to be activated from the disabled list June 24, the first day he is eligible. ... Pirates LHP Francisco Liriano is scheduled to play catch Thursday for the first time since sustaining a strained left oblique June 10 and going on the DL. ... Phillips' string of 43 consecutive plate appearances without a strikeout, the longest active streak in the majors, ended when he fanned in the seventh. ... Cincinnati RHP Alfredo Simon (9-3, 2.95 ERA) opposes Pirates RHP Edinson Volquez (4-5, 3.89) on Wednesday night.
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