LONDON: The lure of reaching the Champions League quarter-finals for the first time will weigh heavily on Manuel Pellegrini's mind as Manchester City and Chelsea prepare for a heavyweight FA Cup fifth-round clash on Sunday.

With City flying to Ukraine to face Dynamo Kiev just 24 hours after Sunday's showdown with Chelsea, the FA Cup tie could not have come at a worse time for Pellegrini, who is reluctant to field his strongest side.

“I think it (the FA Cup) is a serious competition and not a competition you can throw away," said the Chilean, whose side were beaten at home by the Premier League's top two, Leicester City and Tottenham Hotspur, in their last two matches.

"But at this moment... the chance to try and get to the Champions League quarter-final for the first time, I think it’s a case where we are going to prioritise."

While both teams will line up at Stamford Bridge on the back of defeats, Chelsea are no doubt aware that the Cup presents their best chance of ending the season with a trophy.

Hovering in the bottom half of the Premier League is bad enough but a 2-1 defeat at Paris St Germain on Tuesday has left Chelsea in danger of going out of the Champions League at the last 16 stage -- with the second leg to come on March 9.

Hiddink had led Chelsea on a 12-match unbeaten run since taking over from the sacked Jose Mourinho in December but that streak ended on Tuesday when he was forced to reshuffle his back four for the PSG clash after captain John Terry was ruled out with a hamstring injury.

Asked if Terry would return for the City game on Sunday, Hiddink said "Difficult."

Holders Arsenal will take on second tier Hull City on Saturday as they try to take another step towards becoming the first club since Blackburn Rovers in 1886 to win the FA Cup three years in a row.

It has been a quarter of a century since Arsenal's north London rivals Tottenham Hotspur won the Cup but Mauricio Pochettino's men will be eager to continue their high-flying league form when they host Crystal Palace on Sunday.

While Spurs and Arsenal are chasing a league-and-cup double, with both teams trailing Premier League leaders Leicester City by two points, Manchester United's chances of landing any domestic silverware lie solely with the FA Cup.

The managerial axe has been hovering above Louis van Gaal's neck for several weeks and, with rumours of former Chelsea boss Mourinho waiting in the wings to take over, the Dutchman knows he cannot afford any more false moves with United.

Saturday's league defeat by Sunderland dented United's hopes of securing a Champions League place next season and, should they lose to third tier Shrewsbury Town -- the lowest ranked team left in the FA Cup -- on Monday, Van Gaal is likely to be denied any further stay of execution.

In other fifth-round matches, Bournemouth host Everton in an all-Premier League tie, Watford play second tier Leeds United and West Bromwich Albion and West Ham United travel to Championship sides Reading and Blackburn Rovers respectively.