PHOENIX -- Winning streaks are made of little things, such as tagging up at first base and advancing to second.

That play by Chris Young on a routine flyout set up what proved to be the deciding run in Arizona's 4-3 victory over the Oakland Athletics on Sunday, the Diamondbacks' season-high fifth win in a row.

"The play of the game for me was Chris Young tagging up," Arizona manager Kirk Gibson said. "One out and generally you're not going to tag up on that play, but he recognized what was going on. He surprised (center fielder Collin) Cowgill a little bit."

Jason Kubel followed with a single for his second RBI of the game, and 12th of the six-game homestand, to put the Diamondbacks up 4-2 in the fifth.

Joe Saunders (4-4) held Oakland to one earned run over six innings. Scattering seven hits, striking out five and walking two. Young singled twice and scored both times and Aaron Hill had a two-run single as Arizona completed a three-game interleague sweep of the A's. The Diamondbacks have won seven of eight to climb to .500 for the first time since they were 14-14 on May 5.

Arizona had lost 15 of its last 21 home games before going 5-1 on this home stand.

"It's definitely nice to get the sweep here," Saunders said. "We haven't played very well at home this year, so it's nice to turn the page on that and give the fans a chance to have something to cheer about."

Travis Blackley (0-2), in his third start since being claimed off waivers from San Francisco on May 15, gave up three earned runs and six hits in 4 2/3 innings. He also had a nasty welt on his left hip after taking a line drive off the bat of Ryan Roberts in the second.

David Hernandez struck out the side for Arizona in the eighth, then J.J. Putz tossed a perfect ninth for his 13th save in 16 opportunities.

Arizona's Paul Goldschmidt singled in the third inning to extend his career-best hitting streak to 17 games.

The Diamondbacks scored three times in the first. They loaded the bases with one out on singles by Young and Justin Upton and a walk to Goldschmidt. Kubel bounced to second in what looked to be a sure double play, but shortstop Cliff Pennington dropped Jemile Weeks' throw to the bag and all runners were safe as a run scored.

"I just missed it," Pennington said. "A double play gets you out of the inning."

On the next pitch, Hill singled to left to bring in two runs and Arizona led 3-0.

An error also figured in Oakland's two-run fourth. Consecutive doubles by Jonny Gomes and Brandon Inge made it 3-1, then Josh Donaldson singled with two outs to left. Kubel's throw to the plate got there well ahead of Inge and catcher Henry Blanco made the tag, but the ball came loose and the runner was safe, slicing the lead to 3-2. Blanco was charged with an error.

Young said he "just took a chance" when he decided to tag up and go to second on Upton's fly out to center.

"Cowgill has a pretty good arm," Young said. "But sometimes I feel like if I can be aggressive on it, he still has to make a perfect throw."

Young scored from second on Kubel's single, sliding in just ahead of Cowgill's throw.

Oakland made it a one-run game again in the seventh on a pinch-hit RBI single by Seth Smith. The A's had runners at first and third when Inge grounded out to end the inning.

The A's, who came to Arizona after taking three of four at home from the Texas Rangers, fell to a season-worst nine games below .500. Two of the three losses to the Diamondbacks were by one run.

No matter, manager Bob Melvin said.

"A bad series," he said. "Any time you get swept it's a bad series."

Game notes Arizona has Monday off before beginning a rough six-game interleague trip with three stops in Texas and three against the Los Angeles Angels. ... The Athletics take Monday off, then begin a three-game series at Colorado. ... Arizona improved 5-1 in interleague play. ... The A's were swept for the third time this season, the second time on the road. ... Kubel has a team-high 36 RBIs.