Crystal Palace are reportedly considering sacking Oliver Glasner as manager just days after he announced he would leave the club at the end of the season. Chairman Steve Parish has been left angered by Glasner after he claimed he felt "completely abandoned" by the club's hierarchy in the wake of Saturday's Premier League defeat to Sunderland at the Stadium of Light.Glasner confirmed ahead of Sunderland's match that he will part company with the Eagles in the summer. He told reporters: "A decision has already been taken, months ago. I had a meeting with Steve [Parish, chairman] in October, the international break. We had a very long talk, and I told him I will not sign a new contract. We agreed at the time it was the best to keep it between us. It's the best that we could do that and keep it confidential for three months. But now it's important to have clarity, and we had a very busy schedule so that's why we didn't want to talk about it. Steve and I want the best for Crystal Palace. I told Steve [that] I’m looking for a new challenge. It’s my feeling after everything. I told him in October it’s nothing to do with the transfer window. I hate if something is written that is not true it’s tough for me to respond. We have a great relationship and always talking what’s best for Palace."Yet Glasner's exit could come far sooner with Palace now considering axing him as boss, according to Sky Sports. Parish has been left "bemused and angered" by Glasner's comments after defeat to Sunderland. Glasner told BBC Sport: "I feel we are being abandoned completely. I can't blame any player. They did everything they could and this has been going on for weeks and months now. We have 12, 13 players from the squad available and we feel no support. The worst thing is selling our captain one day before playing a Premier League game.  We are preparing, it's the first (full) week we are training since September, and then we are selling our captain one day before a game. So I have no understanding of this. I have always kept my mouth (shut), but I can't because I have to defend these players, because it was the 35th game today. Yes we get under pressure here and we are unlucky. But again, you can't react, we can't help them, it makes it really tough." Looking for smarter football bets? Get expert previews, data-driven predictions & winning insights with GOAL Tips on Telegram. Join our growing community now!Glasner has been frustrated after seeing key players such as Eberechi Eze and Marc Guehi sold, while there is speculation that Jean-Philippe Mateta could also depart this winter. Former England striker Alan Shearer thinks Glasner's departure is now imminent. He told BBC's Match of the Day: "I get his frustration. But then again you look at Crystal Palace as a business, they're going to lose a really, really good player [Marc Guehi] for nothing at the end of the season. So for him to get 20 million now in January, then I get that situation also. But for him to come out and say that again and go against his bosses then there's only ever going to be one outcome. But also by the way. He's given them a great time. He's delivered trophy that they've craved all of their life, all of their career. Supporters have never seen them win that. So they've had that great time as well, you know, so he'll always be looked upon very fondly. But for me, I'd be very surprised if he's still there next week."Add GOAL.com as a preferred source on Google to see more of our reportingGlasner will leave Crystal Palace as a legend after guiding the club to a first major trophy by beating Manchester City in the FA Cup final. The victory also gave the Eagles a first taste of European football but the club must now look for a replacement. Crystal Palace's next game is against Chelsea in the Premier League, but it remains to be seen if Glasner will still be in charge by the time that match rolls around in a week's time.