Ejaria moved to the Stadium of Light for the remainder of the season in January and impressed while completing the full 90 minutes in central midfield of the Black Cats' 1-1 draw with Millwall on Saturday.
A thigh issue has restricted the England U20 international to making only three starts for Coleman's side, who sit bottom of the second tier.
However, the Sunderland boss likes what he has seen from the Reds' Academy graduate, who has made eight first-team appearances for Liverpool.
"Ovie's come to us with a little problem with his thigh. He's played the first few games then missed a couple. He's a good player," Coleman said.
"It's hard for him because he's come out of U23 football playing for Liverpool in games where they dominate and come to us, bottom of a brutal league, which is very physical, but he's coped very well. He's very brave in possession.
"He's done well but there's more to come from him. I think he'll get better and better with the more games he plays but he's a good player."
Six other Liverpool loanees were also in action over the weekend.
Sheyi Ojo came on as a substitute as Fulham secured a crucial 2-1 victory over fellow Championship promotion hopefuls Derby County, while Divock Origi started Wolfsburg's 2-1 loss to Bayer Leverkusen.
Allan Rodrigues de Souza featured as Apollon Limassol beat AEL Limassol 5-1, but Connor Randall suffered disappointment as Hearts were defeated by Motherwell in the quarter-finals of the Scottish FA Cup.
Elsewhere across Europe, Pedro Chirivella and Taiwo Awoniyi played in losses for Willem II and Royal Excel Mouscron respectively, with the latter also being sent off late on.