Jack Ross says Lewis Morgan knows how hard he will have to work to get into the Sunderland side.
The 22-year-old has joined Sunderland from Celtic on loan until the end of the season.
Ross and Morgan worked together with spectacular results at St Mirren last season, and the Black Cats boss says Morgan 'welcomes the challenge'.
“I worked closely with Lewis for several years during my time at St Mirren, and his progression at that time was terrific.
“I’ve been very open and honest with him about how hard he will have to work to get into our team, as we have some very good players, but he’s welcomed that challenge.
“He’s still young but he’s an exciting player, and I know exactly what he’s capable of.”
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Morgan says he hopes to contribute to 'something special' at the club this season.
“I’m joining coaching staff I’ve worked with before, and once I got the opportunity to speak with them, my decision was made," he said.
“My game is based around scoring and creating goals, but I obviously also try to work hard for the team, and that is the most important thing.
“Something special is happening at the club this season, and hopefully I can contribute to that.”