JUPITER, Fla. - If the Red Sox send Jose Iglesias back to Pawtucket now, they may have some explaining to do.

Iglesias has emerged as the best shortstop in camp, with another sparkling defensive play and a three-run triple in the eighth inning against the Cardinals Thursday.

Josh Beckett , who pitched three strong innings in the 9-3 loss, was the beneficiary when Iglesias robbed David Freese in the second inning. Iglesias made a diving, backhanded stop on his knees, then got up and made a perfect throw to first base.

“Yeah, he’s pretty sick,’’ said Beckett. “I can see why they gave him all that money.’’

Beckett played with another slick-fielding shortstop, Alex Gonzalez, for seven years between Florida and Boston, and was asked if Iglesias compared.

“I haven’t seen Jose enough,’’ said Beckett. “I know I saw Alex Gonzalez for a long time. He was pretty good, pretty special.

“It’s nice when they make the great play, but I think when a guy hits a ball that hard, if he’d have missed that, I think I would have been able to understand. It was hit pretty hard.’’

Manager Bobby Valentine is getting used to seeing terrific defense from Iglesias, and Thursday, Iglesias tied the game at 3-3 in the eighth with the triple.

“His other at-bats were decent, too,’’ said Valentine. “His rhythm is very good. He’s getting close. He’s also playing under control and starting to dispel some of the things that were said about him in the past.’’

Beckett stretched out to three innings, working mostly on his changeup, and didn’t give up a run.

Against what was essentially the Cardinals regular lineup, Beckett allowed a two-out single by Rafael Furcal in the first inning and a two-out double by Matt Holliday in the second.

Beckett was pitching on three days rest rather than the usual four because Andrew Miller was scratched with elbow soreness.