Watford defender Tommie Hoban has joined on a season-long loan deal, while former Hamilton, Hibs and Partick Thistle goalkeeper Tomas Cerny has been brought in as cover for Joe Lewis on a one year-deal.
Hoban, 24, has made more than 50 first-team appearances for Watford since being handed his debut at the age of 16 by Malky Mackay, and spent time on loan at Blackburn in 2016-17.
“The last three years have been difficult with injuries, I’ve had a bit of bad luck,” Hoban told RedTV.
“I’m over that now, I’m feeling fit and hoping this is the start again, that this is going to kick-start my career. To be at a big club like Aberdeen it’s the perfect place to do that.”
Watford reportedly have an option to recall the former Republic of Ireland Under-21 cap in January.
“First and foremost Tommie’s an excellent defender,” Derek McInnes told the Dons website.
“It’s well known that we’ve been in the market for another defender and to get a player of his quality from Watford is a great piece of business.
“Although he can play anywhere in the defence, centre-back is his preferred position.”
Speaking about the arrival of Czech ‘keeper Cerny, 33, McInnes revealed an injury sustained by one of the club’s younger goalies had quickened the search for another custodian.
“When we made the decision to allow Danny Rogers to go out on loan, we had been looking at potential options to provide cover for Joe Lewis and the injury to young David Craddock at Inverurie on Monday evening accelerated that process,” the Dons boss said.
“We’re delighted to bring in a player with such experience and who was so willing to get the deal done. Having Tomas as cover will allow Danny to gain valuable match experience at St Mirren.”