People still seem to have some confusion about what position Bailly was playing. I'm sure Bailly is one of those people.
However this is our average positions from the PSG match and I think it shows that he was mainly in a 3 man CB position only slightly wider than Lindelof was towards leftback.
I havent seen anyone suggesting Lindelof played leftback...
After Young had no help with Di Maria and Bernat doubling up down the left wing several times for a 20 minute period where Bernat scored 1 and had another shot straight at De Gea, I remember Young screaming and pointing Bailly out to the right when the Bernat overlap past Di Maria was happening after that point.
Bailly did indeed come out and mark Bernat a few times before being subbed.
I dont know if Bailly was supposed to be doing that all along or if Young, as captain, instructed Bailly to go out there because we'd already been punished heavily for Young having a lack of support from the 2 inside right players - McTominay and Bailly were closest to help. And whatever we were doing wasnt working.
Bernat's 2nd attempt was on the 20th minute, Di Maria had 1 shot from the left and won a corner on that side and soon after Bailly was subbed on the 36th min