MINNEAPOLIS -- The Minnesota Twins suddenly have a glaring concern about closing games for the first time since Joe Nathan took over in 2004.

Tests on Nathan's right throwing elbow have revealed a significant tear in the ulnar collateral ligament, an injury that could require season-ending Tommy John surgery. Nathan's 246 saves over six seasons are the most in the majors during that span.

The Twins shared the grim news Tuesday in Fort Myers, Fla., before their exhibition game against the St. Louis Cardinals. General manager Bill Smith said the plan is to first give Nathan time to let soreness and swelling subside -- and build strength in the muscles around the joint -- before a final decision about surgery.

In the meantime, a second opinion will be sought from Dr. James Andrews, the noted surgeon who removed bone spurs and chips from the elbow in October. The ulnar collateral ligament is replaced in the Tommy John procedure, which typically takes 12 to 18 months to recover from.

The Twins are looking at the strong possibility of a season without closer Joe Nathan, right. AP Photo/Nati Harnik

Nathan will try to pitch again in two weeks. If he can't, the four-time All-Star will have surgery. His season then would almost certainly be over, perhaps putting his status for next year in question, too.

An emotional Nathan said he's prepared to try to pitch through pain.

"If I'm able to go out there and throw, then I'll definitely give it a shot," Nathan told reporters in Fort Myers. "The only reason that I would get a surgery done is if I'm just unable to go out there."

It is possible to pitch through the injury.

"I could be one of those guys. I might not be," Nathan said.

But if his elbow hurts like it did on Saturday, when he first felt discomfort and was removed from an exhibition game against the Boston Red Sox?

"Then there's just no chance," Nathan said.

Nathan and the Twins initially believed this weekend he was just dealing with general stiffness and soreness. He flew to Minnesota to meet with team physician Dr. Dan Buss on Monday.