Watford reportedly scouted Nantes right-back Enock Kwateng on Saturday – but Southampton also appear to be interested in the Frenchman.
Goal reports that both Premier League clubs – and a mystery German club – sent representatives to the Ligue 1 clash at the Stade Lious II as Monaco scrambled out of the relegation zone following a 1-0 win over Les Canaris.
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Kwateng is understood to have been the target and the 21-year-old had a relatively successful game as he generally contended well with the Monaco wingers, although Rony Lopes did set up what turned out to be the winner from Gelson Martins.
The full-back looks set to leave Nantes in the summer with his contract due to expire at the end of the current campaign.
A new right-back would not appear to be a pressing need for Watford but Southampton are very much on the lookout for one after allowing Cedric Soares to join Inter on loan in January – with a view to a £9.5million summer move.