Chelsea and Manchester United reportedly both had scouts in attendance to watch Lyon striker Moussa Dembele during his side's Coupe de la Ligue clash with Brest on Wednesday.
Chelsea are understood to have made Dembele one of their top transfer targets for the January window, with manager Frank Lampard reported to have £150m at his disposal after their transfer ban was reduced.
The Blues have already reportedly offered Olivier Giroud plus £40m for the 23-year-old, but the Daily Mail claims that they could now face competition from Premier League rivals Manchester United.
United have repeatedly been linked with a new striker since the start of the season, having failed to bring one in last summer following the departures of Romelu Lukaku and Alexis Sanchez.
Representatives from both clubs watched Dembele score in the 3-1 victory over Brest, taking his tally for the season up to 13 across all competitions.
The French youth international has previous experience of British football having spent time with Fulham and Celtic before joining Lyon in 2018.