SAN FRANCISCO -- Pat Burrell is back in the National League, back in a pennant race and back to being his old productive self.
"He wants it really bad. That's what we need right now, guys stepping up and having that hunger," pitcher Barry Zito said. "Every game is huge."
Burrell also made a perfect relay throw from left field that saved an early run for the Giants, who will finish this series Thursday before a weekend showdown with the first-place San Diego Padres.
San Francisco remained 2½ games behind San Diego in the NL West after the Padres beat Pittsburgh.
"This is what you play for," Giants manager Bruce Bochy said. "You talk about this in spring training. You want to be in it. We haven't accomplished anything yet."
Rowand's 10th home run of the year, which came in the sixth, gave him seven consecutive seasons with double-digit home runs.
Burrell has been quite an addition since joining the Giants on June 4. Over his last 15 games, he is batting .356 with 10 of his 16 hits going for extra bases. That includes three home runs. His eighth home run of the year leading off the eighth came off Justin Berg (0-1).
Burrell, 33, feels rejuvenated with the Giants after a disappointing start with Tampa Bay.
"Getting the opportunity to come here, first, I'm very thankful for it," he said. "And then to be able to contribute and get back into a pennant race, I really couldn't ask for anything more than that, so I'm more than excited to be here and hopefully we can continue to roll."
Sergio Romo (5-3) recorded five outs for the victory, while All-Star closer Brian Wilson pitched the ninth for his 33rd save in 36 opportunities. Wilson and San Diego's Heath Bell share the major league lead in saves.
Marlon Byrd and Tyler Colvin each hit solo home runs for the Cubs, with Colvin's seventh-inning drive tying the game.
"That was an embarrassment for me to give up the home run and give up the lead," Zito said.
Chicago's Blake DeWitt cut his upper lip when he crashed into Giants catcher Buster Posey in the second on the play started by Burrell on Welington Castillo's double. Castillo got a hit in his major-league debut and first at-bat.
"We've played two games that were clean and we lost," said acting Cubs manager Alan Trammell, filling in while Lou Piniella is helping his ailing mother in Tampa, Fla. "Burrell was a big thorn in our side on some bad execution of pitches. Those are some of the growing pains hopefully we learn from."
Zito gave up a season-high 10 hits in 6 1/3 innings. His winless stretch extended to five consecutive starts despite being staked to a 3-1 lead. The lefty has only one win in 11 starts since June 12, going 1-4 during that stretch with six no-decisions, including three straight.
This game marked only the third time during the stretch that the Giants backed the 2002 AL Cy Young Award winner with more than three runs.
Chicago starter Tom Gorzelanny allowed eight hits and four runs over six innings. He struck five but left with a no-decision for the second time in three winless starts following a season-high four-start winning streak.
The Cubs scratched third baseman Aramis Ramirez about an hour before the first pitch with a sore left ribcage. Jeff Baker started in his place.
The Giants acquired infielder Mike Fontenot from the Cubs before the game, so all Fontenot had to do was walk between the two clubhouses and switch uniforms. He was available off the bench for San Francisco.
Giants OF Andres Torres stole third for the sixth time this year, most in the NL. ... Chicago announced that LHP reliever John Grabow is done for the season. Already on the DL since June 29 with a sprained left knee, the pitcher tore the medial collateral ligament while on a rehab assignment in the Arizona League. He is scheduled to meet Monday with the team orthopedist in Chicago to discuss his options, and surgery is possible. The hope is that Grabow will be ready for the start of spring training 2011. He was 1-3 with a 7.36 ERA in 28 appearances this year. ... The Giants activated INF Eugenio Velez from the DL and optioned him to Triple-A Fresno. Velez was struck on the head July 25 by a foul ball while in the dugout against Arizona. ... The Cubs still don't know how long 1B Derrek Lee will stay on the bereavement list. He has been spending time with his ill grandfather in his native Sacramento and can't play before Friday.