Colon, whose debut was delayed by an oblique injury, allowed two runs on six hits, walking two and striking out four for his first Major League win since June 14, 2007. He gave up runs in the third and fifth innings, both delivered on soft hits, but he pitched out of further trouble in both innings -- and then saw his new teammates score four runs in the bottom of the fifth to make him a winner in a 74-pitch effort.
"The veteran felt like a rookie again," said catcher Jason Varitek, whose solo homer keyed the big fifth inning. "Probably more so because there is previous history of expectation on Bartolo. The young guys don't have as much expectation. When they throw well, they get a big pat on the back. When they don't, well, they're not ready."
Colon, the eighth starting pitcher for Boston this season, showed that he's still ready.
Wrapping up his night, the right-hander saw the Sox take the lead for good and set him up for his 147th big league victory. Almost fittingly, the first of those wins also came at Fenway Park, on June 7, 1997, while he was pitching with Cleveland (where he was a teammate and close with current teammate Manny Ramirez).
"I'm very excited about the opportunity to get out here and contribute," Colon said. "I'm very happy with the way I pitched tonight."
His manager was happy, too.
"I thought he looked fine," said Terry Francona, who cited "a couple of misfires" early before things settled down. "It's a good beginning."
"I thought he threw the ball great," said Varitek. "The big man had a huge smile on his face when we all got in here. I mean, this is pretty big for him to make his way back."
Colon wants to throw more strikes -- he threw 46 on Wednesday -- when he makes his next start, on Monday night in Seattle.
"He's going to work off his location, changing his tilt, mixing in a few changeups," Varitek said. "He threw some good sliders, elevated his ball a few times. [He] did good, did real good.
"Tossing 94 is pretty good. You've got to remember, this is his first outing. He's still building strength. This is a good first step. ... He's going to help us."
Said Royals manager Trey Hillman: "He threw his other pitches, but he located the fastball pretty good for his first start. He pitched to both sides of the plate effectively."
Before the game, Francona said that he was hoping Colon could give the Sox a boost the rest of the way.
"Sometimes you need to catch a break, and maybe this will be our break," he said. "Everybody's looking for something, and pitching's hard to find. This guy seems excited to be here, and you know what? We're kind of excited to have him here."
Colon, signed by the Sox in Spring Training after elbow trouble ended his proud stay with the Angels, topped off at 95 mph, averaging 89-92 mph.
For the first time in the three wins over Kansas City, Boston had to come from behind on Wednesday night.
Jacoby Ellsbury led off the bottom of the first with a home run off losing pitcher Brett Tomko (2-5). But the Sox trailed, 2-1, before Varitek (who has five two-hit games in his last six) led off the fifth with his sixth homer of the year and the 154th of his career, tying him with George Scott for 15th place on Boston's all-time list. Julio Lugo and David Ortiz drove in runs, with a single and sacrifice fly, respectively, and the final run of the inning scored on a Ron Mahay wild pitch.
Ellsbury's third hit, his steal of second (No. 19) and Dustin Pedroia's third hit made it 6-2 in the seventh.
Four Sox relievers worked an inning each to nail it down, though Mike Timlin allowed a run in the ninth.
The Sox, who close the homestand on Thursday afternoon before heading west, opened a two-game lead in the American League East on a night they scored six runs even though the 3-6 hitters combined to go 1-for-13, with Ortiz's sac fly, two double plays and five strikeouts.