By Tony Massarotti, Boston.com Columnist

Between them, Josh Beckett and Jonathan Papelbon will count for $29 million on the Red Sox' record payroll this year. And yet the men who once stood as the bookends of the Boston pitching staff might now serve as the biggest questions entering this go-for-broke season.

Maybe it was only fitting, then, that on the day the Red Sox identified Beckett as the No. 4 starter in a five-man staff, Papelbon went out and got slapped around in an 8-5 victory over the New York Mets at City of Palms Park. The Red Sox have rebuilt themselves over the last two winters with the acquisitions of, among others, John Lackey, Adrian Gonzalez and Carl Crawford, turning over the nucleus of their roster in hopes of reclaiming superiority in both the American League East and all of baseball.

Not so long ago, Beckett and Papelbon were the nucleus around whom the Sox were built, at least with regard to the pitching staff. In 11 combined appearances during the 2007 postseason, Beckett and Papelbon went 5-0 with four saves and a 0.89 ERA. In 40.2 innings, the two allowed 24 hits and 6 walks while amassing 42 strikeouts, the kind of dominating numbers that explain why the Red Sox were unbeatable at the beginning of any series and unbeatable at the end.

"I feel like I'm still locked in on my mechanics, just a tick off,” Papelbon told reporters yesterday during a spring in which his ERA now rests at 12.60. "I'm not searching. I know exactly what's going on in my delivery, and for me, it's not a big deal at all, because it's just a minor little detail for me."

Maybe so.

But the truth is that the Red Sox now have doubts about two of the more important members on their pitching staff and we all know it.

Let's start with Beckett. No matter how you slice it, the Red Sox' decision to place him fourth, ahead of only Daisuke Matsuzaka, speaks volumes. Whatever the real explanation for the move, the Red Sox are now at a point where they feel they need to protect Beckett, bring him along slowly, ease him into things. They are treating him far more like Dice-K than they are Jon Lester. A year ago at this time, Beckett's future with the Sox was front and center, the team ultimately signing him to a four-year, $68 million contract (an average of $17 million per) that has yet to even begin.

Now Beckett is going fourth, perhaps to extend his spring, maybe to grant him a favorable matchup at the start of the season. Yesterday, manager Terry Francona said that opening Beckett up against a wretched Cleveland team was "a good place to start," which is the kind of thing a manager might say about a promising young pitcher. The obvious difference is that Beckett has 112 career victories and the ability of a veteran staff ace, a reality that tells you just how much Beckett has regressed in recent years.

Forget about how you and I see Beckett. That is the Red Sox now see him, based on their actions and comments.

If Beckett's contract had been up this spring, is there any doubt the Red Sox would allow him to enter the year without a deal?

"Just like I would always feel -- like he would back me up,'' Beckett told reporters yesterday when asked about the decision to open with him as the No. 4 starter. "I back him up on his decision as well."

As always, give Beckett credit for that. He never has expected anything to be handled to him and he never will. But the simple truth now is that he has to earn his way back to the top of the Boston rotation.

As for Papelbon, there is obviously some question as to whether, under different circumstances, the Red Sox would want him in camp this spring, too. As things stand, Papelbon will be a free agent at the end of the year. There has been almost no indication that the Red Sox have any interest in re-signing him. Over the winter, the Sox were rumored to have pursued, among others, Mariano Rivera and Rafael Soriano. They signed Bobby Jenks. Papelbon's name surfaced in more than one trade rumor, another factor that suggests the Red Sox would have unloaded him had they been able to get something close to fair value.

Instead, Papelbon returned to the team following easily his worst season as a major league closer. Once regarded as a sure thing, he blew as many saves last season (eight) as he had blown in the two previous years combined. The rate of walks he issues has climbed as steadily as gas prices (now up to 3.76 per nine innings.) Papelbon really has not been the same since October 2008, when the Red Sox leaned on him heavily in the postseason and when he might not have been able to pitch in Game 7 of the American League Championship Series had the situation called for it.

The good news? Thanks to the depth on the Boston pitching staff -- namely, the presence of Jenks and Daniel Bard -- the Red Sox might not need Papelbon as much as they once did. Given the development of Lester and Clay Buchholz as well as the presence of Lackey, the same is true of Beckett. And yet, if the Red Sox are to be as dominating this season as they could be, for them to claim the 100 victories Beckett spoke of upon arriving at spring training, they will Beckett and Papelbon the way they once did.

They need to restore the brass bookends that once framed their entire staff.