Jack Colback said that the drive of the club to reach the Premier League was one of the main reasons that he opted to return to The City Ground.
The midfielder, who spent the second half of last season with The Reds, returns on a season-long loan deal from Newcastle and also said that the support of Aitor Karanka played a big part in him wanting to come back.
He said: "I'm delighted obviously. It took a bit of time getting it finalised but I'm very pleased to be back.
"To get promotion is one of the reasons I came back. Also the support of the manager during off-season. He expressed his feelings about wanting to get me back.
"Obviously when I was here first time round, I enjoyed my time here. A great set of lads and the manager has shown a real ambition to get this club in the Premier League and that is something I want to be part of.
"I think the level of the signings that he's made highlights the ambition. I think there's a real buzz around the club at the moment and I'm just looking forward to getting into it."
The 28-year-old admits that he isn't too far behind the rest of the squad in terms of his fitness levels and is ready for the hard work to be prepared in time for the season's kick-off.
"Yeah I'm alright," he said. "Well I think, I'll see it on the first day of training I suppose. I kept myself in decent shape whilst we were off-season. I certainly carry a good level of fitness so I'm sure I'll be fine.
"It's not far until the start of the season, a couple of weeks off now. The boys have already been working hard, they've been back a while now obviously picked up a few wins in the friendlies, which doesn't mean too much but I'm sure everything is in place come that first game of the season; I'm sure we'll be ready."