Saints’ hopes of European qualification will take another twist tonight as West Ham take on Manchester United in an FA Cup quarter-final replay.

United are currently fifth in the Premier League, with West Ham behind them in sixth.

Three victories in four games for Ronald Koeman’s side has seen them close to the gap to the Hammers to just two points.

Saints are desperate to qualify for Europe via the league, having had a taste of Europa League action at the start of this season.

However, as it stands only the top six are guaranteed European places.

It could stretch as far as seventh though if the FA Cup winners have already qualified for Europe via their league position.

As it stands, if either United or the Hammers won the famous old competition that would be the case, but with Louis van Gaal’s men slightly ahead in the table they would seem a safer bet.

The other semi-finalists – Watford, Crystal Palace and Everton – are all but certain to finish outside of the top six.

With the summer move to the Olympic Stadium moving ever closer, the visit of 11-time FA Cup winners United to Upton Park for a final cup tie cannot get any bigger - according to Bilic.

"It is the final FA Cup tie at the Boleyn Ground," he added.

"It's Manchester United and it's the quarter-finals, so it can't be any bigger an occasion. We are of course fully motivated and want to go through.

"We have played them twice this season at Old Trafford and drawn both games. Now, it's the first time we will play them at home and it's an important game. We then play them at home in the final Premier League game here, which will also be massive.

"Wednesday's game is massive for them and massive for us. Okay, they lost their last game 3-0 but they are Manchester United and they have great players.

"For their standards, of course, they've not been very consistent but they are still above us in the table, and they are very capable of beating any team on their day."

West Ham will be without Diafra Sakho for tonight’s game.

Bilic revealed the Senegal striker suffered a minor knee injury in training which is expected to keep him out for a week.

Andy Carroll is likely to retain his spot in attack having scored a hat-trick in Saturday's draw with Arsenal, and Bilic has insisted he will not rotate his squad despite a trip to Premier League leaders Leicester at the weekend.