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It’s a sight Red Sox fans have seldom seen: closer Jonathan Papelbon heading to the dugout after being replaced in the ninth inning – as he was Sunday in Boston’s last game of the season, when the Angels completed a series sweep.

In the end, they couldn't close the deal.

Despite having one of the best closers in the game – no reliever had better postseason numbers coming into the 2009 playoffs than Jonathan Papelbon – the Red Sox lost in stunning fashion Sunday afternoon at Fenway Park.

Papelbon was asked to get the final four outs in a 5-2 game. From the start, it was clear it would not be easy. The first pitch he threw was lined into right-center field by Juan Rivera, allowing both of the pitcher's inherited runners to score.

It all seemed academic after the Sox tacked on an apparent insurance run in the bottom of the eighth.

But after Papelbon got the first two batters in the ninth and went up 0-2 on the Angels' No. 9 hitter, the unthinkable happened. Base hit. Walk. RBI double. Intentional walk. Two-run single.

With that, Vladimir Guerrero, who had one RBI in his previous 19 postseason games, had knocked Papelbon out of the game and the Red Sox out of the postseason. Scattered boos came from the seats of once-friendly Fenway as Papelbon left the game.

Sox fans spent a good amount of time this season murmuring about Papelbon's work as a closer.

While he finished tied for fourth in the league with 38 saves and was the winning pitcher in the All-Star Game in his fourth straight year on the AL team, things didn't seem to come quite so easily as they once had. There was a certain amount of angst when he took the mound.

Papelbon walked 24 batters in the regular season, one more than he had in 2007 and 2008 combined.

His 1.15 WHIP (walks and hits per innings pitched) was the highest of any season in which he pitched exclusively in relief, the first time it had been more than 1.00.

Papelbon's struggles against the Angels were in stark contrast to the masterful performance of Daniel Bard. The rookie came into the game in the sixth with the bases loaded and nobody out. A double play and a pop fly later, he was back in the dugout with a three-run lead. He followed that up with a 1-2-3 seventh inning.

Bard, a big right-hander who lights up the radar gun with 100-mph heat, has the stuff to become a closer.

The question is, how soon will that be? It is a question fans have been asking quietly throughout the second half of the season.

Papelbon made more than $6 million this season and is due for another large bump in salary during offseason arbitration. It's unlikely the Sox will tie him up to a long-term contract worth $50 million or more, not when they have a youngster like Bard under wraps for the next six years.

Would the Sox consider trading Papelbon before he reaches free agency in two years? There was a time when that was unthinkable, but no longer. Teams are constantly in search of top-flight pitchers to finish off games, and elite closers rarely become available in their prime. Boston undoubtedly could get a lot for Papelbon and still have the heir-apparent in their midst.

General Manager Theo Epstein certainly will not make any decisions in the next few days. He did not become one of the best general managers in the game by overreacting to a playoff loss.

"That was an impressive performance by (Bard)," Epstein told reporters Sunday. "He answered whatever questions anyone might still have about him."

That may be true, but many fans will wonder if he's the answer to the questions they might have about who will handle the closer duties for the Red Sox in years ahead.

Tom Caron is the studio host for Red Sox broadcasts on the New England Sports Network. His column appears in the Press Herald on Tuesdays.