ARLINGTON -- The first-pitch sinker buzzed in at 95 miles per hour, jetting uncharacteristically upward and inward. Mitchell Boggs wanted it low. Instead, it was high, perhaps even a tick above the strike zone, where Mike Napoli took a vicious swing and launched it into the left-field stands.

"My job right there was to come in and leave those guys on base and give our guys a chance to win the game," Boggs said after Napoli's three-run home run led to Sunday's 4-0 World Series Game 4 loss for the Cardinals. "I wasn't able to get it done."

Normally, that assignment might have belonged to Fernando Salas, Octavio Dotel or some other right-handed member of manager Tony La Russa's bullpen. But with two men on base in the sixth inning and the Rangers threatening to rip Game 4 open at the seams, La Russa turned to Boggs and his power sinker, hoping to record two outs with one pitch.

"I thought it was a double play waiting to happen," La Russa said.

Instead, it was a home run waiting to soar. Aiming low and inside, Boggs missed with his location by at least a foot, buzzing his sinker to the northeast corner of the strike zone. A proven high-ball hitter, Napoli drilled it to left field, plating both inherited runners and prompting La Russa to regret his choice of pitchers.

"It looked like it was a bad decision," the manager lamented. "He just missed and Napoli didn't."

"It's a good pitch to hit," Napoli said. "As a hitter you try to look for pitches up, up in the zone, and that's what I do."

That reputation was precisely why La Russa had turned to Boggs, the resident sinkerballer on his bullpen staff. Outside of Marc Rzepczynski, a left-hander who would have played to Napoli's strengths as a righty hitter, none of La Russa's options boasted a higher ground-ball ratio than Boggs this season at 51 percent.

Jake Westbrook led the club's right-handers at 59 percent, but did so exclusively as a starting pitcher; La Russa was wary of asking Westbrook to enter in the middle of an inning. The only other right-hander with a better ground-ball ratio than Boggs was Lance Lynn, who was unavailable after throwing 47 pitches in Game 4.

So La Russa called upon Boggs over Salas, Dotel or even closer Jason Motte, believing he could turn a two-on, one-out jam into an inning-ending double play. Instead, Boggs turned it into a Series-complicating three-run home run when he missed his location to Napoli.

Such was the risk inherent to Boggs, who had allowed a double to Napoli in their only other career meeting. The right-hander had already been struggling this October, allowing at least one run in three of his six appearances, after spoiling his strong start to the regular season with a poor second half.

But still, visions of ground balls tempted La Russa in World Series Game 4.

"You've got to come in and make a better pitch than what I did," Boggs said. "Certainly I made the pitch with conviction and everything I had, and I felt like I was going to get him out right there. But you've got to give him credit. He was ready for it and he jumped all over it."

"I know Boggs has a good sinker," Napoli said. "I was looking for something up and kind of had an idea they were probably going to try to pound me in, and I just got a pitch up that I could handle."

What continued to irk Boggs afterward was that the mistake came on a night when he otherwise felt strong. The results seemed to prove it -- after Napoli's home run, Boggs allowed just one additional hit over 1 2/3 innings, striking out three of the other five batters he faced. He hit 96 mph on several occasions, relying heavily on his power sinker.

But neither he nor the Cardinals could forget the one that did not sink.

"With my sinker, I feel like I can get a ground ball from anybody," Boggs said. "I just left it up."