SEATTLE -- The Seattle Mariners have Hall of Fame first baseman Tony Perez to thank for the end of their slide.
All because of a lesson about not sliding.
Perez's son, Mariners designated hitter Eduardo Perez, remembered Pop's rule to not slide into third base when the opposing shortstop is trying to throw you out.
The younger Perez stayed up on Saturday. That forced a surprised Alex Gonzalez to plunk his short toss off Perez's back for a tiebreaking, two-base error and the decisive run in the Mariners' 5-2 win over the Boston Red Sox, spoiling Kason Gabbard's major league debut.
"I was taught you just don't slide in that situation, to make it a tougher throw," Perez said.
When asked who did the teaching and when, the 36-year-old Perez said: "I grew up around this league."
Perez's heads -- make that body-up -- play and Felix Hernandez's seven strong innings gave Seattle just its second win in seven games. Boston's five-game winning streak was snapped, trimming the Red Sox's lead in the AL East over the New York Yankees back to 2½ games.
Boston's league-best defense -- performing better than any Red Sox fielders in 56 seasons to date -- betrayed Gabbard and reliever Julian Tavarez in the decisive sixth and seventh innings.
Gabbard, 24, allowed three runs -- two earned -- and eight hits in his 5 1/3 innings while slinging the ball from over the top, nearly sidearm and many angles in between. He walked two and struck out three in just his sixth start above Double-A.
The Mariners knew so little of Gabbard, they scrambled to find their only scouting report on him -- from 2004, when he was at Class-A Sarasota.
"He was poised ... I was very impressed," Red Sox manager Terry Francona said of Boston's 29th-round pick in 2000.
Gabbard's day turned with one out in the sixth. First base umpire Larry Poncino ruled that David Ortiz, playing his first two AL games at first base this season this weekend, did not have his toes on the base while stretching to catch third baseman Mike Lowell's throw. That allowed Perez to reach on Seattle's seventh hit.
"It seemed like it was called a little late," said Lowell, who hit his 13th home run in the second inning to give Boston the early lead. "David didn't look like he stretched all that much ... it was so routine.
Said Perez: "His foot wasn't on the bag ... It was a break."
Carl Everett then singled on Gabbard's 99th pitch, prompting Francona to replace Gabbard with Tavarez. Ace Curt Schilling was one of the first to greet Gabbard (0-1) with a congratulatory high five.
"It's an honor to be here. I took advantage of it," said the Vero Beach, Fla., native, who was pitching in front of his mother, father and sister.
Kenji Johjima hit Tavarez's third pitch slowly on the ground. Gonzalez raced in and shovel-tossed the ball toward third base but off the top Perez's back. The ball bounded past Lowell toward the Boston dugout while Perez rumbled home with the go-ahead run.
Gonzalez stomped into the infield dirt in frustration after his fourth error of the season.
"The only play for me was to third base -- but the runner didn't slide," Gonzalez said. "I made a perfect throw."
Boston entered the game leading the majors in fielding percentage, something it hasn't done over a full season since 1950.
"It was the right play," Francona said. "It was a huge play in the game."
In the seventh, Gonzalez ran out under Adrian Beltre's pop fly in short center field. The shortstop then bailed on the catch attempt with a knee-first slide toward charging center fielder Coco Crisp. Crisp shied away from the play while the ball fell between the two for a single.
After Tavarez walked Richie Sexson to load the bases, Perez slapped a single to score Willie Bloomquist and Beltre, making it 5-2.
"Nobody called for it," Gonzalez said of the popup.
Those misplays allowed Hernandez (9-8) to win for the sixth time in eight decisions. He allowed two runs and four hits in seven innings. Hernandez walked two, struck out six -- and wanted to throw more than his 100 pitches. But manager Mike Hargrove stuck to the Mariners' plan to limit Hernandez's innings to under 200 this season.
"I'm getting used to it," Hernandez said, playfully. "But, no, I don't like it."
Seattle took a 2-1 lead in the second after Gabbard walked the .225-hitting Everett. With two outs, Yuniesky Betancourt hit an infield single and Gabbard walked Adam Jones to load the bases. Ichiro Suzuki then sliced a single on a 1-2 pitch to score Everett and Betancourt.
Boston tied it in the third on Ortiz's league-leading 92nd RBI, a two-out single after Crisp had singled and stole second.
Rookie Mark Lowe, two weeks removed from Double-A, pitched a perfect eighth. J.J. Putz finished for his 19th save in 22 chances.
- Gabbard was the ninth pitcher 25 years old or younger to appear for Boston this season.
- The Red Sox placed RHP Tim Wakefield on the 15-day disabled list before the game to make roster room for Gabbard. The move is retroactive to Tuesday.
- Everett made his first start of the season in LF in place of team RBI leader Raul Ibanez. Hargrove said he wanted to rest Ibanez because of "nicks."