Earlier this week, Celtic fans said goodbye to goalkeeper Fraser Forster, as the England international moved to Southampton following a plethora of interest from the Premier League and yonder in his services.The England international will undoubtedly leave a gap behind in the Bhoys starting line up but his departure has seen the Scottish champions collect a cool £10million.That's big money for the Parkhead club, and the best way to spend it would be on a talismanic entity who could bring Celtic's performances to a whole new level - especially in the Champions League.Thus, here's FIVE signings, all relatively expensive but all high quality, that Celtic should consider spending the Forster fund on.

Fraser Forster

[/ffc-gallery]

DAVID MARSHALL

David Marshall

In regards to a direct replacement for Fraser Forster who can match the now-Southampton goalkeeper's immense quality, I suggest Celtic turn their attentions to Cardiff City's David Marshall.

The 29 year-old former Bhoy, who rose through the Parkhead youth ranks and made 35 league appearances before leaving for Norwich in 2007, made more saves than any Premier League keeper last season, as detailed below:

Marshall stats

Talismanic performances from the Scotland international, such as the one below, became common practice last term as the Bluebirds failed to stave off relegation:

//www.youtube.com/embed/KV-ncC7Czwo?autoplay=1&loop=1&playlist= KV-ncC7Czwo

Resultantly, Marshall was expected be snapped up by one of his many top flight suitors this summer, namely Arsenal, Tottenham and Southampton.

But all have sought alternatives to the Scot, making him potentially available to the SPL champions, and Champions League football is certainly a challenge that would appeal to the eleven-cap international.

Price-tag could still be an issue however despite the robust Forster fund. Rumour has it that Cardiff have struck their No.1 with an outrageous valuation to warn off suitors:

CALLUM MCMANAMAN

Callum McManaman

Celtic have already been eying Callum McManaman this summer and the Wigan winger would certainly be a strong addition to Ronny Deila's starting XI.

The 23 year-old burst onto the scene at the end of the 2012/13 campaign, netting three times in the FA Cup as the Latics went on to beat Manchester City in the Wembley final.

Last season saw the former Everton youngster struggle for fitness and form, but he's bounced back this year with a goal and a strong performance against Reading at the weekend:

mcmanaman goals

McManaman is best known for his mixture of industrious and eye for goal, which should put him in good stead in the Scottish top flight. Here's a look at the Englishman's career highlights:

//www.youtube.com/embed/PePGi9nGxr8?rel=0

But it appears the Parkhead outfit will have to make a huge offer, with Wigan boss Uwe Rosler claiming "There's no chance that Callum will go anywhere".

TOM CAIRNEY

Tom Cairney

Another Championship star Celtic should be looking at, especially whilst Kris Commons' contract situation remains unresolved, is Blackburn Rovers midfielder Tom Cairney.

The 23 year-old's stock is rising all the time, in no small part due to an impressive return of five goals and six assists in 37 appearances last season, earning him the Player of the Year award at Ewood Park. Here's a look at some of his highlights from last term:

//www.youtube.com/embed/fAgcMqnLufY?rel=0

He also recorded the second-best pass success rate in the Championship:

Championship passing

And the midfielder will have done his profile no harm with a Man of the Match performance against Cardiff City last friday, typified by this sensational strike:

Rovers only signed the former Hull City star permanently last January after an impressive loan spell and will be understandably reluctant to sell - Cairney plays a big part in their promotion hopes.

But he's a former Scotland U21 who has desires to play for the senior team - Celtic could certainly help him achieve that aim whilst offering the added incentive of Champions League football.

DARREN FLETCHER

Fletcher

Now 30 years of age and having missed the peak of his career after being diagnosed with Ulcerative Colitis, Darren Fletcher's Manchester United tenure is undoubtedly coming to a close.

The Scotland international hasn't been included in Louis van Gaal's expected cull, but he looked disturbingly out of his depth at times last season and is hardly integral to the club's immediate future.

A well known Celtic fan and a 62-cap Scot, Parkhead would be an ideal location for the industrious midfielder to see out his twilight years whilst still enjoying competitive football.

Fletcher may not be the player he once was but there's no doubting his pedigree. Just take a look at the five-time Premier League winner's career highlights:

//www.youtube.com/embed/geBA0Pg1XUU?rel=0

How much United would want for the midfielder remains to be seen, but £5million would be a sensible estimate.

NICK POWELL

Nick Powell

Another Manchester United star known to have caught Celtic's transfer attention before is youngster Nick Powell.

The highly-rated Crewe product impressed in the Championship last year during a term-long stay with Wigan, as viewable below:

Nick Powel

He also netted three times in six Europa League outings. Here's a collection of the 20 year-old's career highlights thus far:

//www.youtube.com/embed/ZfclynD35gY?rel=0

And the 20 year-old, who can feature in attacking and central midfield or as a striker, doesn't appear to be in Louis van Gaal's plans, having been left out of the Red Devils' pre-season tour squad.

No doubt, the England U21 would be a major coup for the Bhoys, but Wigan are keen on his services permanently and Premier League side Leicester City have also been linked: