(The Sports Xchange) - Joe Panik doubled off the right field fence to score Brandon Crawford in the bottom of the 13th inning on Monday, giving the San Francisco Giants a 6-5 win over the Chicago Cubs to force a Game 4 in their best-of-five National League Division Series.

Still down 2-1 in the series, the Giants will send left-hander Matt Moore to the mound on Tuesday. The Cubs will start right-hander John Lackey.

Crawford led off the 13th with a two-strike double off Mike Montgomery, the seventh Cubs pitcher, before Panik followed with his third hit of the game over Cubs right fielder Albert Almora Jr.'s head.

Rookie left-hander Ty Blach (1-0) pitched two innings of two-hit shutout relief to get the win for the Giants.

The Giants had scored three times in the bottom of the eighth inning to take a 5-3 lead before the Cubs rallied in the top of the ninth on a two-run home run by Kris Bryant (3-for-5) off San Francisco closer Sergio Romo.

The homer came immediately after Romo walked leadoff hitter Dexter Fowler.

San Francisco made a bid for a regulation win when Buster Posey (3-for-5) hit a liner into the right field corner with Brandon Belt on base and running on the crack of the bat.

Almora Jr., however, made a diving catch to save the game, then doubled Belt off first base to send the game to extra innings.

Cubs closer Aroldis Chapman had blown the save when he was called upon with two on and no outs in the eighth with Chicago clinging to a 3-2 lead, which they lost when Conor Gillaspie blasted a two-run triple that gave the Giants the lead.

A three-run home run by starting pitcher Jake Arrieta had given the Cubs their lead into the eighth, but they had to call on Chapman after Belt singled off Travis Wood and Buster Posey drew a walk from Hector Rondon to open the inning.

Chapman struck out Hunter Pence for the first out, but then served up Gillaspie's triple to right-center field, scoring Belt and Posey.

Brandon Crawford followed Gillaspie's triple with a single through a drawn-in infield to increase the San Francisco lead to 5-3.

Arrieta held the Giants to two runs in six innings. He gave up six hits and one walk while striking out five.

Madison Bumgarner, who gave up the homer to Arrieta, left for a pinch hitter after laboring through 101 pitches in five innings. He allowed three runs and seven hits, walked one and struck out four.