Rafa Benitez admits Liverpool must keep on spending if they are to mount a realistic Premier League title tilt next season.

Although Liverpool finished nearer to champions Manchester United this season than the previous campaign, Benitez will be well aware his side never looked likely to challenge for top spot.

"Every year you must improve a lot because the other teams are doing the same," he told the club's official website.

"I think Chelsea have just spent £16million on a right-back, even though they got to the (Champions League) final.

"This year we have improved a lot. We signed two or three really good players, and also players who've been good for the club."

Liverpool's season has been played out against an unsettling backdrop of boardroom wranglings and rumours of Benitez being axed.

The Spaniard concedes it has been a difficult campaign on Merseyside but he remains confident the club has made strides to narrow the gap on their Premier League rivals.

"Yes, it's clearly been difficult, special and different, but at the end of the day we tried to manage.

"It's not a perfect season because you need to win trophies but it's not bad because we finished in the top four in the Premier League and Europe.

"Not the best, but not as bad as it could be."