After making 12 appearances for Wrexham since returning to the club on 23 March, Ben Foster announced his retirement from professional football.
Penn spoke to manager Phil Parkinson after Saturday’s game and informed him of his intention.
Foster said: “The honest truth is that this season I’ve not been up to the level I’m asking of myself and I feel now is the right time to retire.
“At the forefront of my mind when making this decision was not only what was best for me but also the club, and making the decision now gives the club every opportunity to assess their options before the window closes.
“Wrexham will always have a special place in my heart.”
Manager Phil Parkinson said: “Ben was a professional model while at Wrexham and did everything we asked of him.
“It takes a big guy to make the decision he has and who really understands this football club, with the timing of his decision.
“I’m sure I speak for everyone, when I thank him for his contribution that went beyond that fantastic penalty save against Notts County to help us gain promotion last season.
“Wrexham was a better place to have Ben Foster around the club.”
Everyone at Wrexham AFC wishes Ben all the best for the future, and will always welcome him to STōK Cae Ras.