The Yankees catcher, who has been sidelined since April 27 with a sore right shoulder, is set to join the Bombers before Wednesday's game against the Blue Jays.
"He had a good day today," Yankees manager Joe Girardi said. "His arm was great today."
Posada tested his shoulder further on Tuesday, throwing out two Phillies Minor League baserunners at second base. It was the third game in which he was allowed to make throws to second base and his sixth extended Spring Training game overall.
"Hopefully everything stays the same and keeps improving from here," Posada said. "That's all I want."
Posada has gone a combined 10-for-26 at the plate with six walks in the six games.
Girardi confirmed after Tuesday's 9-3 loss to the Blue Jays that Posada would rejoin the Yankees on Wednesday, though he and general manager Brian Cashman had yet to discuss when they would activate him from the disabled list. At the latest, they will do so on Thursday.
It is possible that Posada could be added to the roster on Wednesday as a potential pinch-hitter, with the plan to have him catch in Thursday's game against Toronto. Either way, Girardi said, Posada will have a scheduled day off from catching on Wednesday.
Posada, for his part, offered no further comment about when he might rejoin the club. Prior to his stint on the disabled list, he was batting .302 with 11 RBIs in 18 games.
Brittany Ghiroli is an associate reporter for MLB.com. Anthony DiComo contributed to this report. This story was not subject to the approval of Major League Baseball or its clubs.