The Black Cats brought in the 24-year-old centre forward from Zorya Lugansk on the summer window deadline day to strengthen their attacking department.
On Monday, Rusyn was part of Graeme Murty’s Under-21s side, who took on Derby County in a Premier League 2 Division clash, where the Ukrainian provided an assist and won a penalty to help the Sunderland side to a 3-1 victory.
Hewitson stated that Rusyn is a completely different player than they have in the Sunderland squad and stressed that the centre forward is genuinely quick.
The Under-21 assistant boss added that Rusyn is determined to do well for Sunderland and revealed that the player is still lacking physically as he joined the team a few weeks ago.
“He’s different to what we have had; he’s got genuine pace”, Hewitson was quoted as saying by Chronicle Live.
“He wants to do well, he wants to work extremely hard, but he is slightly physically behind the other lads because he has only trained with us for the last couple of weeks so it will take time to get him up to speed.”
Tony Mowbray handed Rusyn his debut against Cardiff City at the Stadium of Light, where he came off the bench in the 88th minute at the weekend.