BOSTON – A year ago, the Boston Red Sox tried to find room for Clay Buchholz in their rotation. Now he’s their best starter.

Buchholz pitched seven shutout innings Saturday night to outduel Zack Greinke and lead the Red Sox to a 1-0 victory against the Kansas City Royals.

“I think it’s just the natural progression of a real good pitcher,” Boston Manager Terry Francona said.

Buchholz (7-3) allowed four hits, three singles, walked four and struck out four in posting his sixth win in seven starts. He’s 3-0 with a 1.32 ERA in his last three outings.

With his name popping up in trade rumors as the club looked for a middle-of-the-order hitter last season, Buchholz bounced between Triple-A Pawtucket and Boston.

On Saturday, he helped the Red Sox rebound after consecutive losses.

“No added stress,” he said of taking the mound with the team on a losing skid. “I just felt like going out and being confident and pitching good enough.”

The Royals entered the night leading the majors with a .282 team average. But they had trouble solving Buchholz’s mixture of offspeed pitches that featured a good change-up and curveball to go with a hard fastball.

“We matched up against a guy who was on top of his game and is one of the best pitchers in the American League,” Kansas City Manager Ned Yost said. “He didn’t make many mistakes.”

The Red Sox lost the first two of a four-game series after sweeping the majors’ best team, Tampa Bay, earlier this week.

The loss snapped the Royals’ three-game winning streak.

Mike Lowell drove in Boston’s run with a grounder.

Dustin Pedroia’s sliding backhanded stab of David DeJesus’ grounder saved a run in the eighth.

“He helps you win. He always does,” Francona said. “We talk about how good he is defensively, but with the game on the line he’s even better.”

Greinke (1-6) was coming off his worst start in nearly two years, when he was pounded for eight runs, seven earned, in 31/3 innings last Sunday against Colorado. He gave up the one run and five hits, walked three and struck out three in six innings.

“It was a battle all day. It wasn’t a smooth six-inning game,” he said. “It was a real stressful game. It will take a toll if every game is like that.”

Boston reliever Daniel Bard stranded a runner at third in the eighth, with Pedroia’s play the key, and Jonathan Papelbon worked a perfect ninth for his 12th save.

“Given the situation, that’s about as big of a play that you can make look routine,” Bard said.

The Red Sox grabbed a 1-0 lead in the second when Adrian Beltre singled leading off, advanced to third on J.D. Drew’s double off the left-field wall and scored on Lowell’s bouncer to second.

Jason Kendall doubled leading off the eighth against Bard and advanced on a sacrifice. After Mike Aviles struck out on a slider outside the strike zone, Pedroia made his play on a sharply hit ball to his right when he slid to one knee, got up and fired to first.

Buchholz allowed one baserunner to third, in the fourth when Aviles advanced from second on Billy Butler’s double-play grounder. Buchholz then retired Jose Guillen on a grounder.