Phoenix, AZ (Sports Network) - Randy Winn homered twice, including the go- ahead solo shot in the ninth, ruining the night when Randy Johnson tied Roger Clemens for second place on the career strikeouts list with a 4-3 Giants win, completing a three-game sweep by San Francisco.

Winn hit solo homers from both sides of the plate for the Giants, who have won six of eight. Tyler Walker (3-3) got the win with a scoreless inning of relief for Barry Zito, who gave up six hits and three runs in six frames.

Chad Qualls (0-5) surrendered Winn's second homer to take the loss. Johnson fanned nine and walked two, giving up two runs on six hits in seven innings for the Diamondbacks. He left with a 3-2 lead, but Tony Pena and Qualls couldn't nail down the win.

The ninth strikeout tied the 44-year-old "Big Unit" with Clemens for second on the career strikeouts list at 4,672. Hall of Famer Nolan Ryan is well ahead of both Johnson and Clemens for No. 1 on the all-time list, with 5,714 strikeouts.

"I did it last year, then I got hurt, then he passed me," said Johnson. "It's kind of a moot point. Winning ballgames is the most important thing ... We need a win right now, so we will look forward to trying to get a win tomorrow."

Justin Upton homered for the slumping D-Backs, who have lost four straight, eight of 10, and were swept for the second time in nine days. The Marlins took three straight in Florida from May 20 to 22. Arizona remains in first place in the lowly National League West, however, where it is the only club with a winning record.

Qualls got the D-Backs out of a jam in the eighth, but Winn took him deep to the opposite field to start the ninth, and the homer to left put the Giants in front.

Brian Wilson tossed a perfect ninth for his 16th save.

Upton gave the D-Backs the early lead when he lifted an inside fast ball into the stands in left-center with two outs and the bases empty in the second, his seventh homer of the season.

Winn knotted the game at 1-1 when he led off the fourth with an 11-pitch at- bat, which he ended by pulling a pitch on the outside corner out to left. Aaron Rowand lined a one-out double to left, and Omar Vizquel brought him home with a single to left, putting the Giants on top.

Conor Jackson's one-out RBI single to left in the fourth tied the game at 2-2.

The D-Backs moved in front with a two-out rally in the sixth. Mark Reynolds worked a walk, and Upton scorched a liner in the gap in right-center for a triple.

Johnson then drew even with Clemens in the record books by fanning Dan Ortmeier to lead off the seventh. He couldn't move into sole possession of second on Thursday, however, as the pinch-hitter Travis Denker lined out, Winn singled to center, and Jose Castillo grounded out to end the frame, and Johnson's night.

Arizona coughed up the lead with shoddy play in the eighth. Pena walked Bengie Molina with one out, and Jackson booted a soft grounder, allowing Ray Durham to reach base. Vizquel grounded out, but Pena beaned John Bowker to load the bases, then walked pinch-hitter Fred Lewis to force in the tying run. Qualls came on for Arizona and fanned pinch-hitter Steve Holm to keep the game tied.

"You have got to be able to capitalize on mistakes and take advantage of them," said Winn. "We were fortunate enough to catch a break in the eighth, and some good at-bats, the Freddy Lewis pinch-hit, does a good job of getting a walk to get the tie."