(SportsNetwork.com) - The San Francisco Giants are losing ground in the National League West, while the Pittsburgh Pirates are gaining momentum in the tightly contested Central.
Something has to give when the two clubs resume a three-game series Tuesday at AT&T Park.
The Giants are two games behind Los Angeles for the division lead and have lost five in a row, including Monday's 5-0 defeat to the Pirates. Madison Bumgarner had won his previous three starts, but was outdueled by Vance Worley and allowed five runs in four innings.
Bumgarner was in the hole early and gave up four runs in the first inning.
"That first inning is probably the most critical for a starting pitcher," said Giants manager Bruce Bochy. "(Bumgarner) is trying to get in sync and get his rhythm, and he was out of his normal rhythm. He had trouble hitting his spots, his stuff was a little flat, and they took advantage of it."
Worley fired a four-hit shutout, struck out three and walked one.
Pablo Sandoval had two of San Francisco's four hits in his club's fourth straight loss at home.
Tim Hudson hopes to right the ship when he takes the mound Tuesday for the Giants and the veteran right-hander is 8-7 with a 2.65 earned run average. Hudson is just 1-5 in his past six decisions and was beaten by Philadelphia his last time out on Thursday in a 2-1 defeat.
Hudson gave up two unearned runs in six innings, struck out six and walked a pair of batters. Hudson is 5-3 in 10 home starts and 6-7 with a 3.18 ERA in 14 career starts against the Pirates.
Meanwhile, Pittsburgh is two games in back of Milwaukee in the Central standings with St. Louis just 1 1/2 games off the pace.
Pittsburgh rode the right arm of Worley in Monday night's win.
"At the start of his third time through the lineup his stuff was still crisp," Pittsburgh manager Clint Hurdle said about Worley. "He made the pitches he needed to make and the guys made some nice plays behind him. He really had some great command out there tonight."
Josh Harrison hit a solo homer, while Gaby Sanchez, Neil Walker, Russell Martin and Gregory Polanco all drove in a run for the Pirates, who have won two straight and seven of 10 games. They are 2-2 so far on a 10-game trek.
Francisco Liriano tries to pitch the Buccos to a series victory when he toes the rubber Tuesday. Liriano is only 2-7 with a 4.18 ERA on the season, but was solid in his previous outing last Wednesday in a 6-1 decision over Los Angeles. He limited the Dodgers to a run and four hits in seven innings.
Liriano, who has allowed one earned run in his past two appearances, is 1-4 in seven road assignments and 1-1 with a lofty 7.20 ERA in two career starts against the Giants.
Pittsburgh took two of three games at home versus San Francisco back in early May and won the 2013 series with the Giants, 4-3.