Great defenders cover the partners, he couldn't do that for Smalling.
The whole team played behind the ball against Liverpool, which means he didn't have to do much against them.
Against City, he lost the header against Iheanacho which rendered Blind being out of position and couldn't stop De Bryne as he skipped past Blind.
As for the 2nd goal in the same game, it was a poor clearance by Bailly which led De Bruyne to have it in a decent position from which he gambled by having a shot at the goal which it the post and Iheanacho scored from the rebound. Again, Iheanacho was supposed to be marked by Bailly, he should have prevented Iheanacho from being first to the ball after the rebound.
I, very well, remember Caftards were blaming Blind for the goals against City and no blame was shifted to Bailly. Just because he is 187cm and strong and fast, Caf love him, while Blind is hated cos he is not a typically English center back.