CLEVELAND -- Asdrubal Cabrera knew what to expect from Cincinnati closer Aroldis Chapman -- fastballs that reach near triple digits on the radar gun.
"You don't ever think home run against him," Cabrera said after driving a 3-1 pitch the other way off the left-hander to right field.
"You just look for a fastball in a zone. You can't try to pull anything. I just wanted to make contact. I don't show my emotion, but when I hit it, inside I was thrilled. I knew it was out."
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It was only the second homer allowed by Chapman (4-3) this year and scored Shin-Soo Choo, who had reached on a one-out single.
"The game goes from jubilation to a downer on one swing," Reds manager Dusty Baker said. "That's a tough one to take."
It was Chapman's third blown save in 11 chances. He has yielded six runs in his last six outings after not allowing any in his first 24 appearances.
"What he was doing early in the year was unhuman," Baker said. "Asdrubal Cabrera's an all-star. He can hit. When they do catch up with Chapman's ball, he's supplying most of the power. Sometime that's going to happen."
Cleveland's third win in eight games vaulted the Indians into first place in the AL Central, one-half game ahead of the Chicago White Sox.
"A great win, very dramatic, very emotional," Indians manager Manny Acta said.
Nick Hagadone (1-0) worked one-third of an inning in Cleveland's second straight win over the Reds after being swept in three games last week in Cincinnati.
The NL Central-leading Reds had a six-game winning streak snapped by their Ohio rivals in a 10-9 slugfest Monday night and appeared to have bounced back before Cabrera connected. They took a 2-1 lead in the top of the 10th when Chris Heisey scored from third base with a headfirst slide on a wild pitch by Hagadone.
That didn't keep Acta from believing his hitters could handle Chapman, who came in with a 1.06 ERA and 59 strikeouts in 34 innings.
"My thought was, 'He's human,' " Acta said. "There's no one in the game where you go and pick up the bats and gloves and go away. I gave them a little rah-rah talk. Sometimes it works."
The Indians needed some encouragement after the way the Reds went ahead.
Pinch-hitter Willie Harris opened the Cincinnati 10th with a double to center off Joe Smith.
Zach Cozart, who had three hits, tried to bunt Harris to third, but Smith hustled to field the ball and throw to third. Harris looked safe, but television replays showed that Harris' front foot slid past the bag as he was tagged out by third baseman Jack Hannahan.
Hannahan then fielded a broken-bat grounder by Heisey at the exact instant that the barrel end of the bat bounced between his legs. Hannahan threw to second to force Harris.
Hagadone, a lefty, came on to face Votto and threw a wild pitch just past the slugger's ear, sending Heisey to second. Votto bounced a 3-2 pitch over Hagadone's head that was fielded by shortstop Cabrera behind second base. Votto hustled to beat the throw for a single, moving Heisey to third.
Brandon Phillips then swung at an 0-1 pitch in the dirt that got past Carlos Santana. The catcher tracked it down and shoveled the ball to Hagadone covering home, but Heisey beat the tag for a 2-1 lead.
The Reds went ahead 1-0 in the first against Josh Tomlin. Cozart hit a leadoff double, took third on a wild pitch and scored on Heisey's infield single.
Cleveland tied it in the fourth. Santana doubled into the right-field corner, moved up on a groundout by Michael Brantley and scored on Casey Kotchman's soft single to center.
Reds starter Mike Leake gave up one run and six hits over seven innings.
Tomlin gave up one run and six hits over 6 2/3 innings in his best outing in five starts since missing three weeks with a strained right wrist. The right-hander walked two and struck out two.
It was Cleveland's third walkoff win this year, second supplied by Cabrera, who singled on a run to beat the Los Angeles Angels on April 27. ... Both managers downplayed an implication by Reds RHP Mat Latos the Indians stole signs Monday night when they pounded the pitcher for seven runs in four innings. "We don't do that," Acta said. "I have enough trouble making sure our kids know our own signs." Said Baker: "You don't really have to steal signs when the ball is down the heart of the plate and up." ... Indians DH Travis Hafner began a jogging and agility program. He had right knee surgery May 31. ... RHP Carlos Carrasco, who had Tommy John surgery Sept. 21, will go to New York with the Indians next week and get checked by his surgeon, Dr. David Altchek. ... Acta gave OF Johnny Damon a day off. Damon was sore after running into a railing trying to catch a ball Monday. ... OF Drew Stubbs (left oblique strain) is eligible to come off the DL Friday. Baker said Stubbs may take batting practice Wednesday and a minor-league rehab assignment is possible.