McCarthy-Scarsbrook transferred from the Broncos to St Helens last season, and now prepares to face his former club who are in top form after Rea took over from Rob Powell.
McCarthy-Scarsbrook said: “They’ve picked up some form in the last few weeks and Tony Rea has made a big difference. But I always knew they were a good team when all their players are fit and on the field.
“Tony gave me my debut and got me started on the road of rugby league and I am grateful for that as I am up here playing for one of the best clubs in the world. I owe him a lot; he got me on the path.
“A couple of the old boys are still there and I will say hello to them. I might even pop to the hotel the night before and see if they want a chat. I can’t wait to play them. I always look for games against London; they are the games I look forward to.”
After two defeats at home to Warrington and away to Wakefield, Saints backed up before the break with a heavy win over Castleford. However McCarthy-Scarsbrook admitted the mood within the squad wasn’t the best, but now says there is an upbeat atmosphere between the players.
He said: “We had two bad losses and we weren’t happy with that. The mood was terrible but now we are upbeat and thinking ahead.
“We have London, Wigan and then into the Playoffs. The intensity will jump them and the boys are raring to go.
“We haven’t peaked yet. We are grinding at the stone. But come the end of the season we will be there.”