Joe Girardi spoke to Chavez before he left Yankee Stadium for the hospital

If there has been one constant with the Yankees during the recent edition of their dynasty, it has been the unparalleled success and durability of their louis vuitton online closer, Mariano Rivera. But Rivera crumpled to the ground in agony Thursday, and all that may have changed. Suddenly, the Yankees’ fortunes for this season appeared very unclear. Rivera, 42, injured his right knee while chasing a fly ball off the bat of the newly recalled Jayson Nix during batting practice before the Yankees’ game against the Royals. As he ran toward the center-field wall, his knee buckled and he crashed to the ground by the base of the wall. Alex Rodriguez, who was waiting for his turn in the batting cage, twice said, “Oh my God,” and Manager Joe Girardi ran out to Rivera. Girardi helped carry Rivera to a cart, which drove him off the field. The Yankees announced a preliminary diagnosis of a twisted right knee after Rivera was examined by Kansas City Royals’ associate team physician, Dr. Joe Noland, and the Yankees’ training staff. He was taken to Kansas University MedWest hospital for a magnetic resonance imaging test. As grim-faced teammates, coaches and Girardi stood louis vuitton womens sunglasses 2012 by, Rivera writhed on the ground in pain, clutching at his right knee. He was wheeled into the tunnel, where he had to be helped into the clubhouse. An outstanding athlete, Rivera fancies himself a credible center fielder, even pleading with Girardi to allow him to play center in a game before he retires. Girardi said he wanted to accommodate Rivera, but was too worried about an injury to let him go through with it. Rivera has been a fixture in center field during batting practice, along with the other pitchers. But he always chased fly balls with more zeal and effort. Before spring training this year, Rivera hinted that this would be his final season in baseball. He said he knew what his decision was, and nothing could make him change his mind. But at the time, he probably did not consider the possibility of a serious injury. Rivera has not been on the disabled list since 2003, when he missed the first 25 games of the season with a groin injury sustained in spring training. Dave Robertson, the excellent setup man, may take Rivera’s place as closer, though Rafael Soriano has also served in the role. Rivera, however, is considered by most to be the greatest closer of all time. Last year he set the record for career saves with 608, most of which came after he replaced John Wetteland in 1997. He has five this season, the last of which came Monday when he threw a scoreless inning in the Yankees’ 2-1 victory over the Baltimore Orioles. CHAVEZ SIDELINED The Yankees placed the reserve infielder Eric Chavez on the seven-day disabled list with a concussion and whiplash, and there is no estimate for when he louis vuitton sneakers for men may return. Chavez was injured diving for a ball at third base on Wednesday night on a play when his head never appeared to touch the ground. But Chavez was groggy after the game and spent Wednesday night in a hospital for observation. He was released Thursday morning and was resting at home, the Yankees said. Chavez remained in the game after the play, even though he felt some mild dizziness immediately afterward. But when he came to the plate later in the game, the symptoms increased, and he had to be helped off the field. Joe Girardi spoke to Chavez before he left Yankee Stadium for the hospital, and he said Chavez said he felt as if he had been in an accident. “He was a little foggy,” Girardi said. Concussions from whiplash can be serious and cause lingering complications that seem to exceed the initial visual severity of the injury. Corey Koskie, the third baseman, was forced to retire after sustaining a similar injury in 2006, and Mets outfielder Jason Bay had what doctors concluded was a whiplash concussion after banging into the outfield wall at Dodger Stadium on July 25, 2010. Bay missed the reminder of that season. Often, dizziness, headaches and nausea are symptoms of concussions, but when the neck is also injured, as with a whiplash concussion, the inner ear 2012 white louis vuitton handbags can be affected, sometimes resulting in vertigo and vomiting. To replace Chavez, the Yankees called up Jayson Nix, 29, who was immediately inserted into the lineup batting ninth and playing left field. Nix, who injured his calf during spring training, played only eight games for Class AAA Scranton/Wilkes-Barre.