Pundits speculate Chelsea have mystery striker lined up to replace Diego Costa

BBC pundits Gary Lineker and Alan Shearer have been speculating over the future of striker Diego Costa this January.

The Brazilian-born Spain international was labelled a "rat" by some Chelsea fans who felt he was partly responsible for Jose Mourinho's recent sacking.

The fiery striker was booed throughout their win over Sunderland in the wake of Mourinho's sacking.

But he bounced back with a brace in the 2-2 draw with Watford on Boxing Day and celebrated by goading fans who had taunted him.

He was booked in that game and misses today's match against Manchester United as a result.

Praising his much improved performance, BBC pundits Lineker and Shearer also speculated he may have played his last game for the club with the January window opening in the coming days.

Mystery replacement lined up?

Speaking on Match of the Day Lineker and Shearer think they may have a mystery replacement lined up.

"I saw in the post match quotes from Hiddink, he was begrudging in his praise and he was almost saying things like 'he might even leave in the window' - he didn't say that but it was just inferred that with him he's emotional, his temperament, you never know," Lineker said on MOTD.

Shearer immediately responded with a wry smile saying: "Maybe they've got someone lined up in January that we don't know about Gary."

Atletico return on cards?

There has been fresh speculation since that Atletico Madrid are not refusing to rule out the possibility of resigning Costa, as reported by RTVE.

The 27-year-old won the Spanish title with Atletico in 2014 before moving to Stamford Bridge for a reported £32 million months later.

The Spain international enjoyed an outstanding first six months in English football and helped the Blues win last season's Premier League crown and the Capital One Cup.

He has struggled to hit those same heights this season, though, as Chelsea put in one of the worst title defences in Premier League history.

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