The openers enjoyed a partnership of 243 runs for the visitors.
United drew 2-2 with Brentford on Wednesday and detected the cases following routine testing of the team. The game was called off as a precautionary measure based on COVID protocols, United said, with identified individuals now isolating pending further tests. "At this stage, we do not expect further disruption around our forthcoming matches, but we will continue to follow Premier League protocols in this regard," the club added.
Liverpool team pay tribute to 97th Hillsborough victim who died this week. Club observes 97-second silence for Andrew Devine, who was ruled a victim of disaster after brain injuries proved fatal
United were due to travel to Deepdale at the weekend.