OAKLAND, Calif. -- When Oakland Athletics shortstop Franklin Barreto hit a towering fly ball to left field in the bottom of the ninth inning Tuesday afternoon, only one guy seemed sure where it was going.

The rookie himself.

"I made really good contact," Barreto said after his moon shot barely cleared the wall for a walk-off home run that lifted the Athletics to a 7-6 victory over the Chicago White Sox.

All-Star Yonder Alonso hit two homers and Matt Joyce added a two-run shot for the A's, who won on the Fourth of July for the sixth consecutive year.

Oakland snapped a six-game losing streak, its longest of the season.

"That was cool," A's starting pitcher Daniel Gossett said of Barreto's second career homer. "It's always in the back of your mind that it can happen. Then to see it happen like that, it's awesome."

The White Sox rallied to tie the game at 6-6 on Melky Cabrera's two-out, two-strike single to left field in the top of the ninth, scoring Tim Anderson from second base. A's closer Santiago Casilla blew the save.

However, one out into the bottom of the inning, the 21-year-old Barreto, playing in only his 10th game since a promotion from Triple-A on June 24, hit his fly ball that seemed to peek over infamous Mount Davis at the Oakland Coliseum before disappearing behind a leaping Cabrera.

"I didn't know," A's manager Bob Melvin said of his initial thoughts after seeing the ball leave Barreto's bat. "I was watching him. He seemed to like it."

The homer came off Chicago's fifth pitcher, Tommy Kahnle, on a full count.

"It's been my dream to help the team win," Barreto said. "It finally happened today."

Casilla (2-3) was credited with the win after blowing his fourth save of the season. Kahnle (0-3) took the loss.

"He put together a pretty good at-bat, fighting off pitches, fouling them off," Kahnle said of the eight-pitch duel. "I thought I'd get him on the 2-2 changeup. He gave that check-swing. But the next pitch ... he hit it. I mean, good for him."

The game featured three lead changes, all the result of home runs.

After Cabrera and Joyce traded two-run shots in the third inning, Alonso's first homer leading off the fourth gave the A's their first lead at 3-2.

Oakland added a second run in the inning on a triple by Barreto, but Jose Abreu countered with a three-run blast for the White Sox in the fifth, putting Chicago back on top 5-4.

The homer was Abreu's 16th of the season, 14 of which have come on the road.

Alonso put Oakland back on top with his second homer in the bottom of the fifth. It also scored Khris Davis, who had singled with two outs.

"It's exciting to see the young guys succeed," said Alonso, who said he had given Barreto some advice after the rookie struck out in the third inning. "I'm not taking none of the credit. I saw something, and then he went out and did it. He's just a special kid."

There was no further scoring until Cabrera's game-extending hit in the ninth.

Neither starter got a decision.

Gossett left with a lead despite allowing five runs in five innings for the second consecutive start. He gave up nine hits and no walks while striking out three.

The first three Oakland home runs came off Chicago starter James Shields, who surrendered three or more homers in a game for the 22nd time in his career. He allowed six runs and six hits in 4 2/3 innings, walking two and striking out four.

Cabrera, Adam Engel, Matt Davidson and Omar Narvaez had two hits apiece for the White Sox, who had won eight of their previous nine games in Oakland.

"All in all, I thought we battled our rear ends off today," White Sox manager Rick Renteria said. "It was nothing they should be ashamed of."

The White Sox outhit the A's 13-8.

NOTES: The A's had lost eight straight at home. ... The majors' top two teams in errors -- Oakland with 76 and Chicago with 68 -- played error-free ball. ... A's 3B Ryon Healy (back spasms) sat out the game after he was lifted in the fourth inning Monday. ... White Sox RF Avisail Garcia (sore left knee) returned to starting lineup after a five-game absence. He went 1-for-4. ... The White Sox had won seven straight on the Fourth of July. ... The White Sox were playing on the road on the Fourth of July for the first time since 2010.