Thomas Partey could join Kieran Tierney in missing the rest of Arsenal’s chase for the Champions League spots after Mikel Arteta said the midfielder had sustained a “significant” injury. Arsenal’s thin squad can ill afford long-term absentees and Tierney’s knee problem, which required surgery and will leave him on the sidelines until at least the summer, was a heavy blow to their ambitions. Losing Partey, who limped off with an injury to his right thigh during the 3-0 defeat at Crystal Palace on Monday night, for the run-in would present a sizeable headache on top of that and Arteta did not sound confident that he would be seen again in the coming nine games. “It’s a little bit ambiguous but he has a significant injury and we’ll have to keep assessing him,” he said. “He will be for some weeks. It could be [that he can play again this season] but it could not be the case, because it’s an area where he had a previous injury as well and he felt it straightaway. He’s not fit.” Arteta hopes his remaining players will rediscover some form against Brighton at the Emirates on Saturday before a testing spell that brings games at Southampton, Chelsea and West Ham along with the visit of Manchester United. The manner of the reverse at Selhurst Park rang alarm bells among the fanbase but he accepts heightened reactions come with the territory in which they find themselves. “The expectations have risen and we have to manage that,” he said of his fifth-placed side, who are level on points with fourth-placed Spurs but have a game in hand. “This is great. It’s much better than being in a completely different position. So we have to embrace that challenge and be aware of that. It’s our job and our responsibility. “[The reaction] is something that has been coming for weeks and [they players] sense it. They sense the change in spirit, the energy around the club and the expectations of the way they are playing and performing. They could see that coming. They have been performing really well, but when a lot of things happen in the same week it’s more complicated. But as well it would be great to learn from what happened on Monday.” Arteta was asked whether he was paying the price for his decision to part company with a number of squad players in January. “But they were players that we did not really use,” he said. “And you put them in the context now, I don’t know how much they would have played. You don’t know, I don’t know.”