Sundays will have a throwback feel all season long at PNC Park in 2013, as the Pirates on Friday introduced a new alternate home uniform that is an update of a classic uniform first introduced in 1970 and worn by the '71 Pirates World Series championship team.

For each Sunday home game next season, the Pirates will don new mustard gold caps and a pullover-style jersey. The front of the jersey has "Pirates" scrolled across the chest in black lettering, outlined in mustard gold, as well as each player's number below the lettering on the left side of the jersey. The collar, sleeves and waistband of the pants will have black, white and mustard gold piping.

These updated jerseys, unlike the ones worn in the 1970s, will include player names on the back to go along with the numbers.

This will be the only change to the Pirates' uniform lineup in 2013, as the home white, road gray and black alternate uniforms will all remain the same.

However, the Pirates also introduced a new batting practice cap. It is black with a gold bill, and the Pirates "P" on the front in gold. The new cap, which was developed by New Era, is lighter in weight and more breathable, with a structured high-crown cap.