Eric Chavez on 7-day concussion DL

KANSAS CITY, Mo. -- Yankees third baseman Eric Chavez was released from the hospital and put on the seven-day concussion disabled list Thursday. Jayson Nix was signed to a major league contract and put into the starting lineup.

Chavez hurt himself when he dove for J.J. Hardy's double down the line in the fifth inning of Wednesday night's game against Baltimore. Chavez went to the plate in the bottom of the inning but felt dizzy, at which point he was removed from the game.

He spent the night at New York Presbyterian Hospital after undergoing head and spine tests.

"He said he felt like he'd been in an accident," Yankees manager Joe Girardi said before Thursday night's game at Kansas City. "He sounded much clearer today than last night."

Nix was starting in left field and batting ninth against the Royals.

Nix was a non-roster invitee to spring training and batted .323 over 18 games, but was sidelined for two weeks with a bruised left calf. Nix has spent the past eight games at Triple-A Scranton/Wilkes-Barre, where he was hitting .233 with four RBIs.

Nix is a career .207 hitter over parts of four seasons with Colorado, Cleveland, Toronto and the Chicago White Sox. He had played in 241 games, but only 11 of them in the outfield.

"You never know -- anything can happen," said Nix, adding he played left field a couple days ago for Scranton. "I came here because I was told there'd be an opportunity to play."

To make space on the 40-man roster, the Yankees transferred right-hander Joba Chamberlain to the 60-day DL. Chamberlain dislocated his ankle in March.

In other news, Nick Swisher hit in the cage and is expected to take batting practice again on the field Friday night. The outfielder had been one of New York's most productive hitters before hurting his hamstring Sunday against Detroit.

The Yankees are still without outfielder Brett Gardner, who remained on the disabled list Thursday even though he was eligible to come off it. Gardner has a strained right elbow.

Girardi said Andy Pettitte will pitch again Sunday, likely for Scranton, after throwing a bullpen session. Girardi said the team has not decided when the veteran left-hander will join the big league club, though it could happen as early as next week.

Pettitte, who is making a comeback after a one-year retirement, reported feeling strong after throwing 96 pitches in an extended spring game on Monday in Florida.

"I think it'll be similar to what he just did," Girardi said of Pettitte's next outing. "I hope he's sharp, he deals, and he comes up and does great things for us."