Koeman watched on as his side fell to a comprehensive 3-0 loss in the first leg at the Philips Stadion on Tuesday evening.

PSV were without their best two players in centre-back Alex and striker Arouna Kone, and then lost forward Jefferson Farfan to injury at half-time.

It was all too much against the power of the five-time European champions, and Koeman has accepted that his side's hopes of a second Champions League semi-final in three seasons has gone.

He said: "I would not know in what way we could believe in anything anymore with such an opponent and with the next game on their pitch.

"The result on Tuesday gives no further possibilities to do something for the second leg.

"The difference in quality between us and Liverpool was too big.

"And the injury to Farfan makes it even worse; we have too many injuries. It is clear that we are in the wrong corner, it looks as if this is supposed to be."

Koeman knew the game was up from the moment John Arne Riise picked up a poor clearance from Timmy Simons 30 yards out and lashed the ball past goalkeeper Gomes.

That made it 2-0, after a first-half header from Steven Gerrard, and was followed by another header, from in-form Peter Crouch.

"The difference was then very clear and if it was up to me the referee could have blown the end whistle at that point," lamented Koeman, whose Benfica side had put holders Liverpool out at the last-16 stage last season.

"Until the first goal of Liverpool [went in] we played reasonably well, we kept being a threat to their defence.

"But when your organisation falls away a side like Liverpool punishes you immediately."

Peruvian marksman Farfan will on Wednesday have an MRI scan on his injury, believed to be to his hamstring.