The Pirates outrighted McKinney to Triple-A Indianapolis on Sunday.
The Pirates designated McKinney for assignment Friday.
McKinney is out of the lineup for Monday's game against the Cubs.
McKinney is out of the lineup for Sunday's game against the Reds.
The Pirates selected McKinney's contract from Triple-A Indianapolis on Monday, Noah Hiles of the Pittsburgh Post-Gazette reports.
McKinney will travel with the Pirates on their road trip to Texas and is expected to be added to the roster prior to Monday's game, Noah Hiles of the Pittsburgh Post-Gazette reports.
McKinney signed a minor-league contract with the Yankees on Friday, Jack Curry of YES Network reports.
McKinney (back) elected to become a free agent Monday.
The Yankees outrighted McKinney (back) to Triple-A Scranton/Wilkes-Barre on Thursday, Joel Sherman of the New York Post reports.
The Yankees placed McKinney on the 10-day injured list Tuesday with a left lower-back spasm.