Both defenders started in the 1-0 loss at Old Trafford on Sunday.
Eriksen said: "I'm happy for both of them.
"Harry has obviously already played a few games, but I think Tyler is an exciting guy – based on the game today and the few times he has trained with us.
"They both work hard and deserve their chances in the team. They can both be proud of what they achieved today."
Defending Hojlund: It's centimetres
The veteran also offered support to fellow Dane Rasmus Hojlund.
He told Viaplay: "It's not just Rasmus. We have a few of us today who have some big chances that need to be scored on.
"Of course 'Ralle' as a striker should be the one who does the most, but today he gets into a few good situations where he's missing a few centimetres. We have enough chances – not just him.
"Of course it wasn't as good as Thursday.
"I actually think we played okay for most of the game, but in the end we weren't good enough. We don't score any goals, and we concede a goal - then it's not good enough at home."