Middlesbrough full-back Tony McMahon believes Nottingham Forest made a "brilliant" appointment in installing Steve McClaren as their new manager.
McClaren replaced outgoing Billy Davies at the City Ground, and inherits a side that missed out in the Championship play-offs during the last two seasons.
"It's a brilliant signing, Forest will be a threat," McMahon told BBC Tees.
"They had a good squad anyway but when Steve adds his players they'll definitely be there or thereabouts."
McMahon, 25, made his Boro debut for McClaren during his time at the Riverside, a spell which included a run to the 2006 Uefa Cup final.
It was his unsuccessful spell with England, missing out on qualification for Euro 2008, that saw the former Derby and Hull midfielder seek employment abroad.
Title success at Twente led to his switch to the Bundesliga, and McMahon is adamant his former mentor has developed as a boss since leaving Middlesbrough in 2006.
"The experience is only going to help. He had the experience with England which didn't work out the way he would have wanted it to, but kept his head down and got another job abroad," he said.
"He did really well, then took a dip and ended up getting the sack [from Wolfsburg], but Steve McClaren being Steve McClaren he was always going to get another job.
"Now the time has come with Nottingham Forest and I think he'll be brilliant for them."