It also was the Mariners' second road win in their past 15, but who's counting?
"Felix stepped up and we took advantage of the other team, which we haven't been able to do," manager John McLaren said. "They opened the door for us and we took advantage of it."
Red Sox starter Bartolo Colon, a longtime Mariners nemesis, was hospitable on this night.
With runners on first and second and one out in the first inning, Adrian Beltre hit a one-hopper back to the mound for an apparent inning-ending double play. Colon fielded the ball cleanly, wheeled and fired the ball to second base -- directly between shortstop Julio Lugo and second baseman Dustin Pedroia.
The ball sailed into center field untouched, Jose Lopez scored from second base and Raul Ibanez went to third. An infield out scored Ibanez, and the Mariners were off and running.
Seattle added another unearned run in the third inning, compliments of another peg into center field by Colon. This time, he tried to pick Ichiro Suzuki off second base, but he misfired and Beltre scored Ichiro with a sacrifice fly to center field.
The Mariners tacked on two more runs in the fourth inning, when Ichiro delivered a clutch two-out, two-run single into left field that hiked the lead to five runs. Seattle had been 0-for-8 with runners in scoring position prior to Ichiro's hit, and Boston was never in it as Hernandez and relievers Sean Green (two innings) and Ryan Rowland-Smith (one inning) collaborated on the Mariners' third shutout of the season.
The series opener was an example of scoring early and adding on.
"That is something we talked about in Spring Training," McLaren said. "That's what we want to do -- jump early, get our pitchers some runs and then add on as the game goes on. You look at most of our wins, we've done that. It's a good strategy; you just got to do it."
Another good strategy is hand the ball to Felix at Fenway.
Hernandez made one start against the Red Sox here last season, had a no-hitter after seven innings and settled for a one-hit shutout. Friday night's game was his first outing at Fenway since then, and he added six scoreless innings.
Among pitchers with an 0.00 career ERA at Fenway since '56, Hernandez is tied with former Indians/Twins pitcher Bill Dailey for the second-longest career scoreless streak. Braves right-hander John Smoltz has the longest such streak at 20 2/3 innings.
It's another kind of streak, a winning one, that most interests the Mariners and their ace right-hander.
The latest run of six scoreless innings was not as dominating as the first nine. Hernandez (4-5, 3.07 ERA) struggled at times, but found an escape hatch each time, most notably in the second inning, when he struck out Coco Crisp with two outs and the bases loaded.
"Getting out of that was important to me and important for the team," Hernandez said. "That was to keep the lead. I made the pitches."
He also stranded two runners in the third inning and another in the fourth, holding the American League East leaders hitless in five at-bats with runners in scoring position.
But he had to work at it, throwing 106 pitches over six innings.
"We're still talking to Felix about using the pitch count," McLaren said. "This is just something that the sooner he gets, the better he's going to be, so he can be in the eighth and ninth inning, where he should be pitching for the win, instead of having to go to the bullpen."
With Hernandez being over 100 pitches, and the Mariners tacking on two more runs in the seventh inning for an eight-run lead, McLaren decided to call it a night for the starter.
Sexson, meanwhile, drove in two of Seattle's final three runs.
He recently spent five days working with hitting coach Jeff Pentland on a new "open" batting stance. His left foot is pointing more toward the third baseman than before.
"I like what I'm seeing," McLaren said.
"It feels OK," Sexson said of the new stance. "Obviously, I want it to get where it feels good every day and every at-bat. There are times when it feels better than other times, and I just have to find a happy medium and stick with it.
"It's a pretty drastic change, going from a closed stance. It's going to take time, but hopefully it will work out and make me better."
The three hits were the most Sexson has had in a game since June 1, 2007. He had gone a career-high 119 games between three-hit performances.