The Steelers rarely make mistakes when they dole out big second contracts to one of their own.

They made a large one with cornerback Cortez Allen, and on Friday they finally admitted it when they released him.

The move, which was anticipated, comes not even 18 months after they signed Allen to a five-year, $26 million contract — and paid him half, $13 million the past two seasons. They decided to not throw more good money after the bad.

By doing so, they avoid paying Allen the $4.4 million salary he was due in 2016, along with the total of $13 million in salaries he was to make over the next three years of a contract he signed just before the 2014 season began.

He will, however, count $4,050,000 against their salary cap this year because of the three years’ worth of pro-rated signing bonus that must be accounted for - and money he already has received. Had Allen been on the roster this year, he would have counted $5,750,000 against the Steelers’ cap in 2016 and more over the next one or two years.

Allen, the Steelers’ fourth-round draft choice from The Citadel in 2011, made steady progress as a special teams player and backup his first two seasons. He then started eight games in 2013 and helped win a late game in Green Bay with an interception that he returned 40 yards for a touchdown.

His performance in 2013, combined with the lack of depth and talent at the position, prompted the Steelers to sign Allen to a five-year, $26 million contract late in the 2014 preseason, one season before he could have become an unrestricted free agent.

His production quickly fell off, and he was benched by the middle of the 2014 season.

Last season was even worse. He was beaten out for the starting job at cornerback by Antwon Blake. Allen played in the nickel in the Steelers’ opener at New England and then never played again.

Allen did not dress for the next five games, and the Steelers finally placed him on injured reserve in October, ending his season - and ultimately his career with them. Allen was rarely seen around the team’s facility after he went on injured reserve.

The Steelers paid him $4,350,000 last season, including a $3 million roster bonus.

The Steelers are looking to again beef up their thin cornerback position in the draft. They lost two of their top four corners in free agency, Blake and Brandon Boykin. They re-signed starter William Gay and backup Ross Cockrell, the only two with NFL experience at the position.