Two fixtures in Britain have been postponed on Tuesday night.
The Steelmen organised two inspections after a period of heavy rain but the match was called off less than two hours before kickoff.
Motherwell stated on Twitter: "Tonight's match with Dundee Utd has been postponed due to a small area on the East Stand side which is waterlogged.
"The club would like to apologise for any inconvenience the call off causes. We tried to give it every chance but it just came up short."
The Red Devils' pitch had been passed playable this morning but worsening conditions resulted in the decision to call the game off.