BOSTON — The offensive peaks and valleys that all teams inevitably go through over the course of a season remain one of the big mysteries of the game of baseball, says Red Sox skipper Terry Francona.

“Sometimes you have to be more patient than you want to be,” he said before last night’s game against the Baltimore Orioles. “It’s just the way the game is. You just can’t figure that out all the way — how guys can get hot, how they don’t. It’s just why the game’s so amazing. Just little things affect a lot of different things. It’s amazing. Then when you do it right and it clicks, it’s fun to watch.”

It took the Sox seven innings last night, but they finally “clicked” for four runs in that frame en route to a 5-4 come-from-behind win over the Orioles at Fenway Park. It marked the eighth time this season that Boston has trailed after six innings and still managed to pull out a victory.

“Every game’s different, and we try to stay focused, one through nine, during the whole game,” said Sox center fielder Coco Crisp, who walked a career-high four times. “You don’t start off all the time with five runs or scoring a run, and eventually we know that our guys are good enough to where we’re going to put up some runs throughout the course of the game. And it just so happened that we had one big inning that put us over the top.”

Baltimore took a 3-0 lead against Sox starter Julian Tavarez. Francona called on the right-hander, who has been pitching out of the bullpen for the last couple of weeks since Jon Lester returned, to fill in yesterday after Kason Gabbard was sent to Texas as part of Tuesday’s four-player trade.

“Julian, giving us five under the circumstances, was pretty phenomenal,” Francona said of Tavarez’s stint, in which he scattered seven hits. “That’s a lot to ask after not starting for two weeks.”

The Orioles took the lead with a two-out solo blast by Nick Markakis in the first inning.

A two-out RBI double high off the left-field wall by Chris Gomez drove in Jay Gibbons in the second. Gomez then scored on Brian Roberts’ line-drive double to left to make it 3-0.

Boston got one run back in the third. After reaching on a leadoff walk, Crisp advanced to third when Orioles shortstop Miguel Tejada committed a throwing error on Julio Lugo’s infield hit and scored on a sacrifice fly to left by Dustin Pedroia.

Although failing to capitalize on a number of opportunities when they had runners in scoring position, the Sox finally rallied in the seventh to take the lead.

Julio Lugo started things off by drawing a walk, which Pedroia followed with a liner to center field.

David Ortiz then drilled an offering by lefty reliever John Parrish off the scoreboard for a double that scored Lugo.

Baltimore intentionally walked Manny Ramirez to load the bases, then brought in right-hander Chad Bradford to face Kevin Youkilis.

Battling through a seven-pitch at-bat, Youkilis doubled to center, driving home Pedroia and Ortiz to give the Sox their first lead.

“He came up big when we really needed him,” Crisp said of Youkilis’ clutch hit, which gives the Red Sox’ first baseman nine RBI in his last five games. “He hit that double, and that was huge. He was fighting throughout the whole game. Each pitch, you could see his intensity, and he was able to come through when the time was right.”

After Gomez made a sharp diving play on a shot down the third-base line by Mike Lowell, Jason Varitek delivered a run-scoring single up the middle to make it 5-3.

Hideki Okajima surrendered a solo blast over the Green Monster to Tejada in the eighth.

But Jonathan Papelbon made sure that would be as close as Baltimore got, retiring the side in the ninth — the last two batters on strikeouts — to record his 24th save.

“What they did was allow us to generate some offense,” Francona said of his bullpen’s effort, which included Kyle Snyder and Javier Lopez combining on a scoreless sixth and seventh. “If we fall back farther, then it’s really a lot to ask. But because they held them at bay, they gave us time to finally get the offense going. ‘Oki’ left one split up, but other than that our bullpen was fantastic.”

cthorn@projo.com