FORT MYERS, Fla. – The contractual stalemate with closer Jonathan Papelbon ended Thursday afternoon, with the reliever agreeing to a record-setting $775,000 salary for 2008.

The deal is the highest-paid salary ever given to a closer not yet eligible for arbitration, eclipsing the previous mark of $750,000 once given to the New York Yankees’ Mariano Rivera.

Papelbon had been holding out for $900,000, the salary given to Philadelphia Phillies first baseman Ryan Howard for 2007 and vowed to accept a renewal of his deal rather than take less in a negotiated figure.

But Papelbon had a change of heart yesterday afternoon and the Sox announced a deal about 90 minutes before their self-imposed 5 p.m. deal.

Before Thursday, every other member of the 40-man roster had agreed to a contract for 2008, and with Papelbon’s signing, the Sox avoided having to renew a single player in a spring in which a host of high-profile young stars were renewed by their teams.

“We think our (salary) structure for pre-arbitration players is fair,” said general manager Theo Epstein, “and ultimately, our players felt the same way. We tend to be generous within reason . . . It’s always nice to reach an agreement. It’s the club’s right to renew, but it doesn’t always feel good for the player.”

Papelbon had gone home before the deal was announced and unavailable for comment.

“He seems to be happy,” said Epstein. “His sights may have been set higher, but I think the more information he was given, the more he understood (the club’s position).”

smcadam@projo.com