The former Juventus winger has impressed in training.
O'Shea told the Sunday Mirror: "We are coming along nicely as a squad.
"Positive signs are there. (Emanuele) Giaccherini looks a real talent, even though he isn't fully fit yet, Cabral looks like he can be a top player in the Premier League and, with Wes Brown coming back after injury, that's like signing a new player.
"There was a lot of upheaval last season and at times we were making headlines for all the wrong reasons.
"But it feels more settled now, even with all the new players that have come in over the summer, and there's a great spirit around the place.