The Giants loaded the bases in the first and stranded two in the second, but Chicago starter Travis Wood couldn't get out of trouble in the third. With one on and one out, Cole Gillespie doubled and Torres followed with a two-run double. Torres moved up on a wild pitch and then scored on Todd Linden's sacrifice fly to open a 3-0 lead.
"It's one of those days where it was a grind at its best," Wood said. "I didn't have anywhere close to my best stuff. It was nice to be able to get out there and get my pitch count up and be able to throw and get ready for the season."
The left-hander will make one more spring start in Houston when the Cubs play exhibition games at Minute Maid Park.
"It's nice knowing you have one more instead of going straight into the season," Wood said. "Even having a day like this is nice because you know how it felt and what you need to work on -- if you weren't finishing or pulling off or something."
The Cubs had a runner at second with two outs in the third when David DeJesus dropped a double into center, which Angel Pagan lost in the sun. The runner scored.
Posey blooped an RBI double to right with two outs in the fourth to make it 4-1.
The Cubs loaded the bases in the fourth, but third baseman Nick Noonan, who has been assigned to the Giants' Minor League camp, made a great diving stop of Alberto Gonzalez's hard-hit grounder and threw in time to end the inning. Noonan doubled with one out in the fifth and scored one out later on Pagan's single.
Wood, who will be slotted into the No. 3 spot in the Cubs' rotation, gave up seven hits and four runs and walked four over four innings.
Dioner Navarro hit his fourth spring home run with two outs and one on in the Chicago sixth to close to 5-3 but the Giants loaded the bases in the seventh against Cory Wade, who is battling for the final spot in the bullpen, and added a run on Pagan's groundout. Joe Panik then hit a potential double-play ball to shortstop Brent Lillibridge, but his throw was low and a run scored on the error. Arias then hit a two-run double.
The Cubs have two games remaining at HoHoKam on Tuesday night and Thursday. They will move to a new spring facility in west Mesa next year.
Up next: Opening Day starter Jeff Samardzija will get his final spring tuneup Tuesday when the Cubs play host to the Reds at HoHoKam Stadium in a night game. Johnny Cueto will start for Cincinnati. It'll be a preview of most of the Cubs' Opening Day lineup as well, with David DeJesus, Starlin Castro, Anthony Rizzo, Nate Schierholtz, Welington Castillo, Luis Valbuena and Darwin Barney starting. The game will be broadcast on Cubs.com.