According to the same source, the player has agreed to join les Bretons on a season-long loan, with the deal set to be wrapped up later today.
The transfer comes as a big surprise seeing as how Premier League sides Stoke and Cardiff were very keen on adding the player to their ranks.
However, Nelson Oliveira has opted for Rennes due to the fact that the Ligue 1 side will give him the best possible chance of securing regular playing time.
The Portugal international has been showing a lot of potential of late, but he has, nonetheless, made just 4 league starts over the last two years.
Oliveira, 21, spent last season on loan at Deportivo La Coruna, scoring 4 goals in 30 La Liga appearances, but it is important to note he only started two of those games.