With the European leagues over for yet another season, the attention turns firmly to the summer of transfer speculation.

Here, we look at three key transfers that could happen as clubs and players alike look for new moves and opportunities.

Could any of these deals happen?

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ROMELU LUKAKU

Champions Chelsea have made former striker Romelu Lukaku their preferred attacking signing this summer, according to the Evening Standard.

The Everton frontman, who left Stamford Bridge on a permanent deal in 2014, is reportedly at the top of manager Antonio Conte’s shopping list, ahead of Real Madrid ace Alvaro Morata.

VERDICT: 8/10

SPORT360 RATING: The 24-year-old feels he has unfinished business at Chelsea, and with 25 Premier League goals this season, he would be a serious attacking threat for Conte’s men. Having rejected a new contract at Everton, it looks likely he will put pen to paper on a long-term deal at Stamford Bridge – should Diego Costa depart this summer.

CHRIS SMALLING

Manchester United will listen to offers for England defender Chris Smalling, according to ESPN.

West Ham and West Brom are said to be battling it out for the 27-year-old, who is under contract at Old Trafford until 2019.

United manager Jose Mourinho is searching for a replacement and the Daily Star claims Real Madrid’s Raphael Varane and Brazil international Marquinhos, who plays for Paris St Germain, are potential targets.

VERDICT: 8/10

SPORT360 RATING: Mourinho has publicly criticised Smalling, and his days in Manchester look all but over. With Slaven Bilic set to reshuffle his defence in the upcoming transfer window, the England international is the perfect candidate to tighten up the defence at the London Stadium.

MICHAEL KEANE

Former Manchester United defender Michael Keane could be an expensive option to bolster the club’s defence, with the Sun reporting Sean Dyche has warned that Burnley are prepared to play hardball even though it would risk the England international leaving on a free next summer.

With United and Liverpool both interested in securing the Englishman’s services, it may prove difficult for Burnley to keep hold of their influential centre-back.

VERDICT: 4/10

SPORT360 RATING: The 24-year-old is said to be keen on a return to Manchester United, and with Dyche willing to release his star man at an asking price of £25million, expect Keane to re-sign for his boyhood club.

What else is going on…

Manchester United prepare for their Europa League final against Ajax after the Manchester tragedy.