Manchester United suffered a shock 3-1 loss to Crystal Palace at Old Trafford – their first opening day defeat for six years.
The Red Devils have now reportedly made contact with the representatives of Porto left-back Alex Telles, according to transfer expert Fabrizio Romano.
Reports on Friday claimed United had agreed personal terms with Brazil international Telles but were yet to thrash out a fee with Porto.
But Romano says Ole Gunnar Solskjaer is considering making an opening bid following the Palace loss.
Solskjaer has been keen on bringing in a left-back throughout the summer, providing competition to Luke Shaw and moving Brandon Williams to backup right-back.
Duncan Castles of the Transfer Window podcast claimed on Friday that Porto had reduced their asking price for Telles from €25million (£22.9m) to €20m (£18.3m).
However, Castles said Solskjaer’s side were still not prepared to pay that much for the 27-year-old.
Meanwhile, Red Devils’ legend Gary Neville was co-commentating on the loss to Palace for Sky Sports.
And the former right-back singled out the centre-back area as the biggest cause for concern.