OAKLAND -- A's right-hander A.J. Griffin knows full well that one bad pitch can mean defeat when you're squaring off against Seattle's Felix Hernandez.
What Griffin might not have known is that a 41-year-old catcher named Henry Blanco can still handle an inside fastball and do major damage.
Blanco, making his Mariners debut, came up in the sixth inning Saturday with the bases loaded and one out in a 0-0 game and tomahawked the first Griffin pitch he saw for a grand slam down the left-field line.
That's all Seattle and Hernandez, the A's pitching nemesis, needed for a 4-0 victory before 24,378 at the Coliseum. And afterward, Griffin was lamenting it big time, particularly since the pitch to Blanco was pretty much where he wanted it.
"If you look at the video, I hit (catcher) John (Jaso) right where he set up," Griffin said. "It's just one of those where you have to tip your cap to him. It was up and in, and he got it. It could have been a little more in, maybe, but it was still a well-placed ball. That's how it goes."
Blanco signed with the Mariners -- his 11th major league team -- Friday after being released by Toronto earlier in the week. He joined Seattle hitting .184 with no home runs. And his last grand slam came May 12, 2000, a span of 13 years and 34 days that represents the fifth-longest gap between slams in modern baseball history.
"Jason Schmidt," Blanco recalled. "That was a fastball, too."
Indeed, Blanco connected off Schmidt when he pitched for Pittsburgh, before coming to the Giants, in the last year of the Bill Clinton presidency.
Earlier in the week, Blanco wasn't sure if he had a baseball future, but Seattle called him Thursday, and he high-tailed it to Oakland.
"I was just hoping I could get a job and show a team I still can play," he said.
And what keeps the Venezuelan going at 41?
"I just want to win a World Series," he said. "I love the game, I have passion for the game, and I just want to get a ring so I can go home."
That might prove a challenge with Seattle, which is seven games under .500 and 9½ games behind the A's in the American League West. But at least he can enjoy catching a star like Hernandez, who did his thing against Oakland once again.
Hernandez (8-4) pitched seven scoreless innings, and while the A's had chances against him in the first, fifth and seventh innings, they couldn't get the big hit to support Griffin (5-6), who matched zeros with the Mariners' ace over the first five innings.
"He seems to make a pitch when he has to," A's manager Bob Melvin said of Hernandez. "He has so many weapons. He's not throwing as hard as he did in the past, but he's got a cutter, a slider, a curveball and a changeup, and he can throw any pitch in any count to both sides of the plate."
Hernandez also beat the A's in the season opener and now has 142/3 scoreless innings against Oakland this year with two walks and 16 strikeouts. He 15-6 against the A's in 28 career starts.
The Mariners as a team are proving to be a bit of a thorn to Oakland in 2013, too. Seattle is 6-3 against the A's and has won two straight at the Coliseum after Oakland had won 11 in at home.
"We get Felix and (Hisashi) Iwakuma every time, it seems like, and (Joe Saunders pitched well (Friday)," Melvin said. "I think that's had a lot to do with it. We haven't scored a whole lot of runs."