Manchester United have been dealt another blow in their efforts to finally sew up a Champions League place with the news that Michael Carrick will miss the rest of the season. Carrick was hugely influential as Louis van Gaal’s side produced their best form of the season to beat Tottenham, Liverpool and Manchester City in a four-game spell. At that point a place in the top four and a return to Europe’s top competition next season appeared a formality and ambitions were set on finishing runners-up behind Chelsea to position themselves for a real tilt at the title next season. But then Carrick suffered a calf injury and his importance to this Manchester United side became even more apparent.

Without the presence of the veteran, assured midfielder, United have lost three matches on the bounce, including a chastening 3-0 loss to Everton and a home defeat to West Brom last time out. Fifth-placed Liverpool now sit just four points back. While with three games remaining that should still be sufficient for United to get over the line, nerves must now be building that an unthinkable second season without the prestige and remuneration of the Champions League could still become a reality.

That the influence of Carrick will be missing for the closing fixtures will only add to that sense of unease. Van Gaal has conceded that he lacks a natural replacement for the England international, going as far as to say that it is one of the areas he needs to address in this summer’s transfer window.

“Carrick is not available, it was more heavy than we thought,” Van Gaal told MUTV. "We tried everything but now we have to think about next season. He shall not play anymore this season, it's better now to focus for him on next season and being fit to start.

“When you see the stats, it's clear that he's very important but that's also because we have only one right-sided holding midfielder. That's what I am saying already in the whole of the season, that our selection is not balanced, and I want to restore that in the next transfer period. The life is not ending at 34, but for a professional football player, it's close by. That's why I have to handle again in that position.”

United visit Crystal Palace on Saturday, when it remains to be seen whether Van Gaal will opt for Daley Blind or Ander Herrera in the deep-lying midfield role. Blind could be freed up from his duties at left-back with Luke Shaw fit to return to action after injury. Jonny Evans is also in contention for a return.

It promises to be a tough assignment for United at Selhurst Park. Although they have lost three matches in succession after achieving their goal of safety, Alan Pardew’s side showed against Chelsea last weekend that they can be a difficult outfit to beat. Crucial to United’s hopes will be whether they can regain their attacking verve. Van Gaal temporarily found the right formula, with Marouane Fellaini excelling as a target-man attacking midfielder, Herrera providing dynamism and Wayne Rooney thriving back up front.

But teams have got wise to Fellaini’s threat and the changes Van Gaal have failed to reap dividends. Robin van Persie returned last week against West Brom but continued to look a fading force. In the second half there was the odd and unimpressive sight of Fellaini playing up front, ahead of both Van Persie and Rooney. Crystal Palace will not be frightened of dealing with a similar prospect on Saturday. Could it now be a stage for the club’s record signing, Ángel di María, to make an appearance in the starting lineup for the first time in more than two months?

Certainly it looks likely to be a pivotal weekend in United’s Champions League ambitions. With Liverpool visiting Chelsea on Sunday, a win for United could see them confirm a top-four berth. Alternately they could be faced with going into the final two games of the season with just a single point advantage and an in-form Arsenal up next.

Manchester United’s remaining schedule
Saturday, May 9 @ Crystal Palace (12.30 p.m. EDT)
Sunday, May 17 vs. Arsenal (11 a.m. EDT)
Sunday, May 24 @ Hull City (10 a.m. EDT)