Middlesbrough head coach Aitor Karanka says Tomas Kalas has solved his right-back quandary following Friday's half-season loan move from Chelsea.
The Czech Republic international, who had been on loan with Bundesliga side Cologne, made his Boro debut in Saturday's goalless draw with Reading.
Kalas, 21, has made four first-team appearances for his parent club.
"He's a very good player for the present, in a position that has created problems," Karanka told BBC Tees.
"With him now we're much better because the position is covered by a very good player."
The right-back berth has proved problematic for Boro since Damia Abella's long-term injury in September, with Rhys Williams, Emilio Nsue and Ryan Fredericks among the players to deputise.
Karanka has utilised his working relationship with Blues boss Jose Mourinho - who he was assistant to at Real Madrid - to sign goalkeeper Jamal Blackman, defender Kenneth Omeruo and forward Patrick Bamford, in addition to new arrival Kalas, on loan this season.
Kalas has already impressed the Spaniard, coming into the side just hours after his transfer to the Teessiders.
"He has shown [against Reading] that he's a good player. He's young but he's experienced. He could play 90 minutes and we now have another week to work with him," added Karanka.
"It's difficult for a player who is not playing and is new in the team but it wasn't a surprise for me as I know him and what kind of player he is.
"He played an amazing game at Anfield last season against Liverpool, so it's no surprise.
"I know from now he's going to improve."