Aberdeen have completed the signing of former Coventry and Leeds striker Noel Whelan on a one-year contract.
Noel Whelan cost Middlesbrough £2.2m four years ago
There had been clubs in the English Championship chasing the 29-year-old, who impressed on trial.
But he said: "I'm aware there were other clubs interested, but I feel this is exactly the kind of fresh challenge I need.
"Aberdeen are an ambitious club and the new management team gave up the chance to be in Europe this season to join."
Jimmy Calderwood and Jimmy Nicholl last season led Dunfermline Athletic to Uefa Cup qualification after reaching the Scottish Cup final.
"They have big plans for the Dons and I'm absolutely delighted that I have the opportunity to be part of them," said Whelan.
Calderwood had feared that he would not be able to afford the Englishman, but Whelan was prepared to take a drop from the kind of salary he could have expected had he remained in his homeland.
"I am here to play football and want to try to bring success back to the club," he said.
Aberdeen start the season at home to Rangers on Saturday.
"Those are the occasions I want to be involved in," he stressed.
"I have had a couple of seasons in the English First Division now and I would prefer a different challenge."
He left Middlesbrough last year for Millwall but then joined Derby County on a month-to-month loan deal.
Calderwood revealed that Aberdeen legend Gordon Strachan had made him aware of Whelan, for whom he paid Leeds United £2m while managing Coventry City.
"His experience will be a great asset to us, both on and off the pitch, and he's a player whose size and strength will give us different options up-front," he said.
"He has worked hard in training, has demonstrated that he really wants to play for this club and I'm really glad to welcome him on board.
"Noel goes straight into the squad to face Rangers here in our opener on Saturday."
Calderwood is also monitoring former Scotland striker Scott Dobie's situation at West Bromwich Albion, who have signed Kanu and Jonathan Greening.
Slovan Liberec forward Lubomir Blaha could also come to Scotland for a trial next week.