Arsenal manager Arsene Wenger's interest in a £24m summer deal for William Carvalho is fraught with complications, including uncertainty over potential wage demands and his co-ownership situation making negotiations problematic.
That is according to the The Telegraph, who make it clear in their report that Wenger is still searching for an imposing physical presence in central midfield and is ready to make Carvalho his top transfer priority thanks to lingering doubts over a swoop for Real Madrid star Sami Khedira.
Carvalho is without question one of European football brightest young talents and has been scouted extensively by Manchester United in the last six months, but its Arsenal that have moved ahead in this transfer tussle and are working hard to close another marquee signing before the transfer window slams shut.
Khedira deal stalls
Wenger is believed to view Carvalho as a more cost-effective option than Khedira, who would command wages in the region of £150,000-a-week thanks to a proven track record at the highest level for club and country.
Khedira's name has been mentioned to Wenger in several press conferences and produced a typically coy response on each occasion, but a poor recent track record with injuries has led Wenger to ask Arsenal chiefs to pursue a move for Carvalho.
That chase is by no means straightforward though, as United have already found out.
Can Sporting keep Carvalho?
For starters Sporting Lisbon only own 60% of Carvalho's registration rights, with the other 40% belonging to the Sporting Portugal Fund, who have consistently claimed a stake in some of the club's top players in recent years and recouped portions of sizeable transfer fees as a result.
Carvalho has a £35m release clause in his current contract but Arsenal are confident Sporting would accept an offer of £24m before the transfer window slams shut, but there's plenty of work to do on both sides before this deal gets done.
Incredible wage difference
The 22-year-old quite surprisingly only earns around £10,000-a-week at Sporting, which means Arsenal could hand him a massive increase on that relatively meagre salary and spend far less than it would take to land Khedira.
That doesn't mean to say Wenger isn't a huge fan of Khedira and wouldn't pursue that deal under the right terms, but his search for a genuine enforcer in midfield has turned to a prospect in Carvalho who has all the tools to become a world-beater for the next decade if his development stays on track.