Since returning from surgery on his left Achilles tendon, Howard has struck out 33 times in 77 at-bats and is hitting .208 with four home runs and 10 RBIs.
He was 0 for 4 with three strikeouts before his game-winner.
"It feels good," Howard said. "I will try to build on it."
There is plenty of building to go. Howard insists that he isn't favoring his leg when hitting and is confident he will get into a groove.
"For me, it's been a timing issue, and I have kind of been in between starting too late and starting too early," he said. "I am just in between, and I have to find a happy place."
Manager Charlie Manuel, a true hitting guru, has had frequent talks with Howard. Manuel believes that Howard has gotten into trouble by not being balanced at the plate.
"At times, he doesn't use his backside, and that is what drives the ball and gives you quick hands," Manuel said. ". . . That is what gives you bat speed."
Like Howard, starting pitcher Cliff Lee experienced mixed results. Lee had the type of performance that has become common during his baffling season - unhittable at times, overly generous at others. He pitched eight innings and allowed four runs, but was hurt once again by the gopher ball.
Lee allowed three home runs, and now has surrendered 18 in 1331/3 innings. He allowed 18 in 2322/3 innings last year.
"The home runs, I have to do a better job of keeping the ball down, keeping it in the ballpark, especially when it is hot here," Lee said. "The ball travels really good, so that is when I have to be more conscious of keeping the ball down and more ground balls."
The Phillies, who are out of the NL East cellar though still 16 games behind first-place Washington, showed some fight, coming back from 3-0 and 4-3 deficits.
They got two runs in the second inning when John Mayberry Jr. scored on a wild pitch and the still-hot Erik Kratz (.379) launched an RBI double.
Utley's solo home run to right field in the fifth tied the score. He has seven home runs in 106 at-bats and is encouraged by his comeback from sore knees. Utley believes that he is driving the ball better than last year.
"I think my at-bats are a little better overall, and I feel stronger," he said.
Arizona broke the tie in the sixth inning with Paul Goldschmidt's 16th home run.
The Phillies tied it in the eighth, with Mayberry as the catalyst. Mayberry got a two-out infield single and advanced to second on a wild pitch. Domonic Brown then hit a ball that deflected off hard-throwing relief pitcher David Hernandez.
There appeared to be time to get Brown at first, but Hernandez's underhanded throw went wide. Mayberry kept running and scored.
Pinch-hitter Juan Pierre led off the Phillies' ninth with a single up the middle off reliever Josh Collmenter. Pierre was sacrificed to second by Nate Schierholtz. Pinch-hitter Laynce Nix was awarded a hit when rightfielder Justin Upton couldn't make a sliding catch.
Upton plays one of the deepest right fields in the game, and it hurt him then and also when Howard came to the plate after Utley was intentionally walked.
Howard's hit fell in front of Upton, and suddenly the Phillies first baseman was being mobbed by his teammates at - of all places - first base.
"It was not the best game for me at the plate," Howard said. "In that situation, I wanted to win the game and I wanted to be in that situation."
It's a situation he's been in before. This was Howard's eighth career walk-off hit, the most among current Phillies.
He hasn't forgotten how to get a big hit. The next step is doing it with more frequency.
Contact Marc Narducci at 856-779-3225 or firstname.lastname@example.org, or follow on Twitter @sjnard.