United's return to form under the Norwegian coach has impressed the Blues assistant coach as they gear up for Monday's FA Cup tie
Ole Gunnar Solskjaer has done "quite remarkable" work at Manchester United since taking charge, according to Chelsea assistant Gianfranco Zola.
United won 10 and drew one of their first 11 games under the caretaker manager before Tuesday's 2-0 Champions League defeat at home to Paris Saint-Germain.
Their improved form since the departure of Jose Mourinho in December has seen United overhaul Chelsea and Arsenal in the table and move into fourth place on 51 points.