Aston Villa are reportedly keeping tabs on Zenit St Petersburg's Nicolas Lombaerts and Mbark Boussoufa of Anderlecht.
Martin O'Neill is set to venture into the transfer market to look for a new defender following the retirement of Martin Laursen.
Lombaerts has emerged as a possible target and the versatile Belgian admits he would be open to an offer from the Premier League.
"I hadn't heard about the interest of the English club, but in the future I would like to try myself in one of the top championships, of course," the 24-year-old told Sport Express.
One stumbling block to a deal may be Lombaerts' fitness as he has only just come back from a long-term knee injury.
He admits his primary focus is on regaining his best form, adding: "Firstly I need to fully recover after my knee injury and return to Zenit's starting line-up.
"Incidentally everything is now fine with the knee. I believe that it will not be giving me any more problems."
Anderlecht midfielder Boussoufa is also understood to have attracted the attention of Villa after an impressive campaign.
Scouts from the club are believed to have watched him in action and reported back positively.
However, the Moroccan is valued at around 10million euros (£8.7million) and the likes of Marseille and Lyon are also thought to be keen.
Boussoufa has also insisted that it would take something special to prise him away from Anderlecht.
"I am prepared to leave Anderlecht only if a big offer arrives from a club with a lot of ambition," he said.