Aberdeen manager Craig Brown says he has been impressed by Icelandic defensive midfielder Kari Arnasan in the club's last two pre-season fixtures.
The 28-year-old scored in Wednesday's friendly win against Inverurie.
Arnasan had been on Hearts' pre-season trip to Italy before joining the Dons on trial.
The midfielder is a free agent after being sacked by Plymouth Argyle last month.
The Iceland international left Home Park after refusing to go without full pay for a seventh consecutive month after the club entered administration.
Aberdeen begin their Scottish Premier League season against St Johnstone on 23 July.