The Atlanta Braves said Thursday that the 38-year-old third baseman tore his anterior cruciate ligament and will need surgery. The estimated recovery time is six months, short enough to be ready for the next opening day - if Jones decides to return in 2011.
He had already said he would consider retirement after a season that's now ended sooner than expected.
"I'm sure as the next couple of days go by, those are things we'll discuss and he'll discuss with his family," his agent, BB Abbott, told The Associated Press. "It's not something he'll decide immediately. He's going to need to hear everything about the injury and rehabilitative process. He'll probably make his decision from there. I can assure you it's not something that's going to be a knee-jerk decision."
Jones was hurt in Tuesday night's game at Houston. He fielded a routine grounder by Hunter Pence, jumped in the air while making the throw to first, then collapsed to the ground for several minutes.
After an MRI exam, Jones met Thursday with the team doctor, Marvin Royster, who delivered the grim diagnosis - and a major setback for the NL East leaders.
"Obviously, he's very, very disappointed. I would almost describe it as numb," Abbott said. "He knows this will be a big blow to the team. Obviously, he has been going very well recently and felt like he was really contributing to the team's success. This is real disappointing for him."
Jones feared something was seriously wrong after he walked off the field gingerly under his own power.
"It's hurt," he said in Houston. "I heard a distinct pop."
The Braves were actually hopeful when the knee didn't swell as much as one would expect after an ACL injury, especially when Jones was able to handle some routine flexibility drills. But the MRI showed a partial tear, plus some stretching of the ligament, making it impossible for him to come back without surgery.
"We were cautiously optimistic," general manager Frank Wren said. "When we got the news this morning, I was actually pretty shocked."
Jones had bounced back from a slow start and was hitting .265 with 10 homers and 46 RBIs for a team that had a 2½-game lead in the NL East on two-time defending league champion Philadelphia. The Braves will have to carry on with Omar Infante and Brooks Conrad sharing third base, though neither has Jones' power.
Coming off a poor 2009 season, Jones got off to a miserable start this year and said in June that he was considering retirement. A few days later, he backed off and said he would wait until after the season to make a decision. He had been playing much better since then, raising his average some 30 points and showing more power.
"There's no denying the presence he had in the middle of our lineup," Wren said. "When you think of the Atlanta Braves, the first guy you think of is Chipper Jones. His presence in our lineup has been increasing based on his performance the last couple of months. He was a force. So, yeah, we're losing a lot."
Wren will look into making a trade to bolster the lineup, but his options are limited since the deadline for non-waiver moves has passed. Besides, he's not sure the Braves could find a player more effective than Infante, who made the All-Star team as a utility player and is hitting a team-leading .330. Another All-Star, second baseman Martin Prado, is expected to take batting practice Friday and could return from the disabled list soon after breaking a knuckle.
Another option isn't likely: Wren dismissed the idea of calling up slugging first baseman Freddy Freeman from Triple-A and moving Troy Glaus back to third base, his original position. He said Glaus just doesn't have the range he did earlier in his career.
"This really doesn't change our first base situation at all," Wren said.
As for Jones, he has to consider whether he wants to keep playing after the second major knee injury of his career. He missed all of 1994, expected to be his rookie season, with the same injury to the same knee. Jones returned to become one of the greatest players in Atlanta history, a six-time All-Star who won the NL MVP award in 1999 and the NL batting title in 2008.
Recovering from a major injury late in his career would be much tougher, perhaps the biggest factor of all when Jones considers whether he should retire. He would also have to work out a settlement with the Braves, who owe him about $28 million in guaranteed money for the next two seasons.
Jones certainly won't be around to help the Braves try to hold off Philadelphia in the final year for longtime manager Bobby Cox, who has already announced he'll retire at the end of the season. Jones, as much as anyone, wanted to send out Cox with his the team's first playoff appearance since 2005.
"There's certainly a part of him that feels like he's let Bobby down, and let his teammates down," Abbott said. "He's really distraught about it."