Rudi Skacel is back with Hearts, but the Czech midfielder is only training with the Edinburgh club so far.
Hearts say the 33-year-old was on the lookout for training facilities and has an accepted an offer to use theirs.
"When we heard that Rudi was back and looking for a place to train, we were only too happy to offer the use of the academy to him," their website stated.
"He has been keeping in shape in Prague and wanted to keep things ticking over during his time in Edinburgh."
Hearts say it was similar to the offer they made to their former goalkeeper, Craig Gordon, during the summer after the Scotland international's release by Sunderland.
However, Skacel, who left Hearts at the end of his contract following their Scottish Cup victory over Hibernian at Hampden Park in May, is helping the club with some of their commercial activities.
The midfielder had hinted last month on Twitter that he could be back in action soon.
Hearts director Sergejus Fedotovas followed that on Facebook by suggesting that his club's supporters could expect "good news".
Manager John McGlynn said that he was in the dark about the possibility of Skacel signing a third time, but now the midfielder has reappeared at Tynecastle.
His 22 September post on Twitter had led to speculation about where his next move would be.
"Relaxing home after the practice," he said. "The season starts for me next week! More than Ready!"
"Talking to clubs, but the decision will be made by Monday! Time to get on the pitch!"
However, he has been quiet on the matter since a post that followed two days later making reference to the 5-1 win over their Edinburgh rivals.
"Thank you for all the messages from Hearts fans - you are the best, but unfortunately I may not have good news for you," said Skacel.
"But, wherever I go, 51 shirt it is."
Skacel, who began his career with Hradec Kralove and Slavia Prague in his homeland, first joined Hearts on loan from Marseille in 2005.
He moved permanently to Southampton then headed for Hertha Berlin on loan before returning to Hearts in 2010 after spells with Slavia Prague and Larissa.