It's approaching that time of year again when Barclays Premier League clubs will be shopping for some bargains to strengthen their squads.

Free transfers are always popular, particularly among directors looking to save money in the current climate.

So who is there available on the continent? Which Bosmans are there to look at and who should clubs not touch?

We take a look at six players available for free this summer.

Serginho Greene

A first-team regular since he joined Feyenoord in 2005, Greene can play anywhere across the backline, an adaptability which is more than useful in the modern game. With his 27th birthday near, he is approaching the best days of his career and has the necessary experience to handle the Premier League. While he may not be on the radar of the elite, he offers strength in depth and would be a useful addition to teams likely to be fighting for survival.

Verdict: Buy

Oguchi Onyewu

The Standard Liege centre-back has been in impressive form again this year and it would be no surprise to see him leave to further his career. The American already has Premier League experience, albeit limited, after his loan spell in Newcastle in 2007.

Since then he has improved as a player in Belgium and was part of the Liege team that knocked Everton out of this year's UEFA Cup and ran Liverpool so close in their Champions League qualifier.

At 6ft 4in he would suit the physical element to the English game and, only turning 27 next month, he could be ready for a step up to a higher level.

Onyewu could represent great value for most of teams in the Premier League; indeed he could easily be one of the bargains of the summer.

Verdict: Buy

Marko Pantelic

With goals hard to come by this season for many struggling clubs, strikers will surely towards the top of most shopping lists. And Serb Marko Pantelic could be somebody for them to look, at especially for teams mid-table and below. He is set to leave Hertha Berlin after he refused to sign a new contract and his goals record is reasonable - 44 in 104 appearances. At 30, though, there does seem to be the perception that he has not really fulfilled his potential.

Pantelic is something of a risk but if a manager could get the best out of him he may be the difference between relegation and survival.

Verdict: Buy

Maniche

The former Chelsea and Porto midfielder is best known for his goal in the European Championship semi-finals against Holland.

He has a wealth of experience having won the Champions League in 2004 - but did not enjoy his time at Stamford Bridge.

After falling out with the management team in Madrid last year, he has since spent time on loan with Inter Milan but has already stated he intends to leave this summer, with Porto said to be interested in taking him back.

Maniche's main qualities are his workrate and stamina. He turns 32 later this year so he may not suit the fast-paced English game while after an unsuccessful stint in London he might not be what clubs are looking for.

Verdict: Avoid

Benoit Pedretti

Once seen as the hier to Claude Makelele, Pedretti is more comparable to Andrea Pirlo in that he sits deep, has great vision and has a great right foot.

The 28-year-old started off at Sochaux, where he captained the side, before moving onto Marseille, Lyon and now current club Auxerre.

Having spent his entire career in France he may look for a new challenge and will need to move soon if he can give his best form to a new club.

Pedretti was a France international in his pomp, but with the emergence of talent like Jeremy Toulalan and Lassana Diarra those days could be over.

He still offers something, though, and will suit a team that likes to pass the ball.

Verdict: Buy

Sebastian Viera

The Argentine goalkeeper burst onto the scene with Villarreal and played an important role in their run to the Champions League semi-finals in 2006. That almost earned him a move to Arsenal, though the deal broke down, and he has since lost his place to Diego Lopez and could be looking for regular football. A good shot-stopper who like many European goalkeepers opts to punch rather than catch, Viera can be erratic and that inconsistency can see expectant fans get on his back, this affecting his confidence. At 26 is relatively young for a goalkeeper and can only improve with time and experience and has an Italian passport, which would help any move to England. In such an important position, though, he is a risk.

Verdict: Avoid