Blackburn Rovers have rejected an offer from Crystal Palace for the services of Adam Wharton.

The Lancashire Telegraph understands that a significant bid has been knocked back by the club for their star player. It's unclear what exact figure has been offered but The Athletic report £18.5million was on the table from the Premier League side.

Wharton has been the subject of intense speculation since breaking into the Rovers first team. Newcastle United, Everton and Wolves were heavily touted as possible destinations in the summer.

Rovers stood firm and did not receive any concrete offers, according to Director of Football Gregg Broughton. Instead, the club secured Wharton to a new five-year contract at the start of December.

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That new deal was to highlight Wharton's rise to prominence in the Rovers squad, rather than a huge indication he will be at Rovers for the length of the agreement, which runs until 2028. The midfielder told The Lancashire Telegraph last month that it does not contain a release clause.

Given his impact at Rovers, it feels like a case of when rather than if Wharton does move on to the Premier League stage. Jon Dahl Tomasson has described the midfielder's technical ability as 'Champions League quality'.

Wharton remains fully committed to Rovers and has never agitated for a move. However, there is also an appreciation from all parties that Premier League opportunities don't come around every day in a short career.

It's understood that a potential sale and loan back is unlikely with Palace keen to bolster their midfield now. Few clubs deal in the January transfer market and an outlay of this significance would be with the intention of Wharton going straight into the first-team picture at Selhurst Park.

It remains to be seen if Palace will come back with a second offer but this is a huge decision from Venky's considering their financial issues. 

Cashflow has a major problem for Rovers in the last 12 months and an offer of around £20m would fund the club for a year, to put the finances into context.

That said, replacing someone of Wharton's quality in the final week of the January window would be nigh-on impossible. They could spread some of the funds around the squad, hypothetically, but prices could inflate with teams knowing Rovers money to spend.