YOU could forgive Graham Potter for just jacking it in himself.Hammers fans protested against their owners and the manager as they endured a third straight home defeat to a London rival.ReutersTyrick Mitchwell was an unlikely matchwinner for Crystal Palace[/caption]PAJean-Philippe Mateta opened the scoring[/caption]PAJarrod Bowen headed in an equaliser just after half-time[/caption]ReutersGraham Potter is under big pressure at West Ham[/caption]Defeat to Crystal Palace will further ramp up the pressure on the beleaguered boss.Whatever Potter tries, however much work is going in, there is little end product on show and few signs of the tide turning.Palace’s glee, as they extended their unbeaten run to 17 games and chanted about lifting the FA Cup last season, only made things harder for the home support.Over 1000 had gathered outside the directors’ entrance ahead of kick-off to demand that owner David Sullivan and vice-chair Karren Brady resign their post.Once Palace took the lead for a second time through Tyrick Mitchell, after Jarrod Bowen’s header had cancelled out one from Jean-Philippe Mateta, Potter was in the firing line.His call to remove the impressive Mateus Fernandes was booed by a majority, before chants of “you don’t know what you’re doing” and “sacked in the morning” from the home end.Potter had dumped struggling summer signing Mads Hermansen in goal to try and turn things around – but it had little impact, just like most things that have been tried at this club in recent years.Despite changing keepers and, supposedly, practicing defending corners all week, the Hammers luck still did not turn.BEST FREE BETS AND BETTING SIGN UP OFFERSPalace had eight first half corners, some of which were scrambled behind before the visitors struck from number seven.Daichi Kamada’s ball in was met by Marc Guehi, whose header was deflected onto the bar. Mateta, Palace’s most dangerous forward who had scored four in three against the Hammers before this meeting, was left unmarked to nod in the rebound from a few yards out.Palace had been far from their best, but did not need to be in the first half.West Ham were offering precious little, any half opening coming more by chance than any identifiable plan.But they emerged for the second half with a sense of purpose at last.Corners have been West Ham’s nemesis early this season, as evidenced by Palace’s opener.But after the break they managed to turn one their way, summer signing Malick Diouf whipping a devil of a ball to the front post where Bowen glanced into the far corner.West Ham’s captain has been the only reliable figure at this club across their last 18 months of struggles and looked desperate to dig them out here.Minutes after the leveller the England man skipped down the right and crossed for Callum Wilson, who couldn’t quite reach the ball.Bowen then drew a near post stop from Dean Hednerson after a flashy one-two with Lucas Paqeuta, whose backheel from the byline teed up the strike.The captain’s drive had finally awoken a sleepy London Stadium which had been so flat for the entire first half.Bowen again found space behind Mitchell and found Paqueta at the far post – his header hooked clear by Chris Richards – before Henderson held a low shot from Kyle Walker-Peters.Just when things were looking up for West Ham, they suffered another sucker punch – delivered superbly by the right boot of Mitchell.Palace had been stuck largely in their own half, but eventually ventured down the right.Richards swapped passes with Daniel Munoz, who appeared to be offside but was not flagged, before laying back to the returning Adam Wharton.The England midfielder’s cross was headed upwards by Konstantinos Mavropanos, falling for Mitchell to rocket past Alphonse Areola on his weaker foot.Palace’s eventual winner caused mutiny to break out from the apathy in the sparse stands for a brief moment as supporters rounded on Potter.Replacements for the former Brighton and Chelsea manager have been considered this week and the board now face a few days of soul searching as to where to go next.They are an ownership usually reluctant to pull the trigger, but there are few signs that loyalty will pay off at the moment.