Manchester United would have reportedly moved for Chelsea's Emerson Palmieri in the latter stages of the transfer window had a deal for Alex Telles fallen through.
The Red Devils finally completed a move for Brazil international Telles on transfer deadline day following weeks of negotiations with Porto.
According to Italian journalist Fabrizio Romano, Ole Gunnar Solskjaer's side had planned for the possibility of missing out on the South American by identifying Emerson as a possible acquisition.
The 26-year-old was strongly linked with a move away from Stamford Bridge over the summer, but the transfer deadline passed with the Italy international still with Frank Lampard's side.
Emerson, who was linked with Juventus, has featured on two occasions in the EFL Cup this season but has not even made the squad for any of Chelsea's four Premier League matches in 2020-21.
Telles will battle Luke Shaw and Brandon Williams for the left-back spot in United's first XI.
