ESPN MLB

PHOENIX (AP) -- Micah Owings isn't a good hitter for a pitcher. He's a good hitter, period.

Owings proved it again Wednesday with an opposite-field, pinch-hit home run that tied the game in the sixth and helped the Arizona Diamondbacks rally from four runs down to beat the Houston Astros 8-7.

"I've been blessed to be able to swing it," Owings said, "so every time I get in the box I do my best to help this team."

Owings, 4-0 as a starter and arguably the best-hitting pitcher in the game, hit the first pitch of the game from reliever Dave Borkowski to the right field seats, a two-run shot with two outs that tied it at 7.

Chris Young followed with a double and then scored the go-ahead run on Eric Byrnes' single.

Owings raised his season average to .421 (8-for-19). A silver slugger winner last year when he hit .333, Owings has five home runs in 79 at bats over his two big-league seasons.

"I don't think you've seen a guy like this," teammate Conor Jackson said. "I mean, Babe Ruth? That's really all that comes to mind. It's pretty impressive."

Comparisons with the Bambino might be a bit of a stretch, but Owings has proven to be another tough out in the prolific Diamondbacks' batting order.

"You have your bench and then you have an extra guy to pinch-hit and a guy you don't mind running up there against righties, lefties, in between," Arizona manager Bob Melvin said. "The way he's been swinging, it wasn't even a tough decision."

The Astros knew to be ready for Owings.

"We rarely go over a pitcher in the meeting when we talk about how to approach the opponent's hitters, but we went out of our way to discuss how we'd pitch to him," catcher Brad Ausmus said. "It was a slider that didn't break like we wanted, but give the guy credit.

"He hit it to the opposite field. You don't see a lot of opposite field homers hit by position players, let alone pitchers," he said.

Owings limped around the bases because he sprained his right ankle Saturday stepping on second after doubling in San Diego. The last pitcher to hit a pinch-hit homer was Brooks Kieschnick on April 22, 2004, for Milwaukee against Arizona.

Arizona (20-8) became the season's first 20-game winner, with a franchise-record 19 of them in April. Arizona won its eighth series out the last nine. The exception was a split of a two-game set with the Los Angeles Dodgers.

The Diamondbacks' lone series loss came in the season-opening games at Cincinnati.

The Astros led 6-2 after two innings against Randy Johnson. Houston scored four in the first, three on Carlos Lee's sixth home run of the season.

Astros manager Cecil Cooper called it "by far, by far" the worst loss of the season.

"I mean, we can't even get the stinkin' pitcher out, we're in trouble," he said. "My goodness, a two-run lead and we can't even get out of the stinkin' inning. That's unacceptable, and it won't happen again."

Johnson, in his fourth start of the season after rehabilitating from his second back surgery in two years, allowed six runs on nine hits in four innings. He struck out two. Brandon Medders (1-0) gave up an unearned run in two innings to get the victory.

Chad Qualls, Tony Pena and Brandon Lyon each threw a scoreless inning to wrap up the victory. Lyon earned his ninth save in 11 tries.

Lyon gave up a single to Kazuo Matsui and a one-out walk to Lance Berkman, but Lee and Jose Cruz Jr. flied out to center to end the game.

Arizona's comeback started with Jackson's solo home run off starter Shawn Chacon to cut it to 6-3 in the third. The Diamondbacks scored two in the fourth to cut it to 6-5, including an RBI double by pinch-hitter Jeff Salazar.

Chacon, in his shortest outing of the season, allowed five runs on seven hits. He struck out seven and walked one.

Houston made it 7-5 in the sixth when Medders walked pinch-hitter Darin Erstad. Erstad took third when shortstop Stephen Drew muffed Hunter Pence's grounder. Pence scored on Matsui's sacrifice fly.

Drew started the Diamondbacks' three-run sixth with a double to left-center. After two outs, manager Bob Melvin sent Owings to the plate, and Borkowski came on in relief.

Game notes

Max Scherzer, who retired all 13 batters he faced -- striking out seven -- in his major-league debut on Tuesday, will start Monday at Philadelphia. ... Houston has lost seven of eight at Arizona. ... Chacon, who entered the game with a 2.45 ERA, has no decisions in six starts.