Royals 5, Giants 0: James Shields pitched a four-hitter and former University of Nebraska standout Alex Gordon homered on Huskers Night at Kauffman Stadium as Kansas City won its sixth straight game.Shields (11-6) improved to 27-15 in August - 13-3 since the start of 2011 - after recording his first shutout of the season and ninth of his career as the Royals moved to within 1 1/2 games of first-place Detroit in the American League Central. Lorenzo Cain, Mike Moustakas, Alcides Escobar and Jarrod Dyson recorded RBIs in a four-run seventh for Kansas City, which extended its lead to one game over Seattle for the final AL wild-card spot with its 14th victory in 17 contests.San Francisco's Tim Hudson (8-9) lost for the seventh time in his last eight decisions and fell to 1-3 with a 2.59 ERA in five starts since the All-Star break after yielding three runs in six-plus innings. The Giants have lost four of their last five contests and 11 of 16 and remain 3 1/2 games behind Los Angeles in the National League West.Gordon blasted a 2-0 fastball out to right-center leading off the fifth to open the scoring. Billy Butler began the seventh with a double, moved to third on Gordon's single and scored on Cain's bouncer through the right side that chased Hudson before Moustakas (double), Escobar and Dyson produced two-out RBI hits.Shields, who was facing San Francisco for the first time, allowed singles in the second, third and fourth, and Joe Panik was stranded at second after doubling to lead off the eighth. Panik became the game's first baserunner to reach second when he walked with one out in the fifth and advanced on a wild pitch.GAME NOTEBOOK: Hudson, who has never had a losing season in his 16-year career, last faced Kansas City on May 14, 2004, earning a 6-2 victory while with Oakland. ... Panik's walk is the only free pass issued in the first two games of the series. ... The Royals improved to 37-11 when hitting a home run.