Bayern Munich have made a second bid, this time in excess of £20m, for Chelsea's Callum Hudson-Odoi, Sky Sports News understands.
Bayern have made the England U19 international their No 1 target in what could become one of the biggest deals of the January transfer window.
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At this stage, Chelsea are yet to respond to Bayern's latest bid.
Bayern's rivals Borussia Dortmund are also interested in Hudson-Odoi, whose current contract with Chelsea expires in the summer of 2020.
Hudson-Odoi joined Chelsea at U8s level and is viewed as one of the finest talents in the club's academy and one of the best players the Blues have produced in recent seasons.
He played a key role in England's 2017 U17 World Cup victory, appearing in all nine matches and setting up three goals in the 5-2 victory over Spain in the final.
Personal terms between Bayern and Hudson-Odoi have yet to be discussed but are not expected to be a problem.
The 18-year-old has found first-team football hard to come by under head coach Maurizio Sarri, making five appearances this season - but only one in the Premier League.