© Getty Images
Reims had the better of things in the first half, but were unable to open the scoring come the break.
After the restart, Lens were a different proposition to the opening 45 minutes, relentlessly pushing forward and causing the hosts' defence no end of trouble.
Riou was in fine form, however, and was able to pull off a series of great saves, while the visitors lacked the right level of incisiveness to make their dominance count.
Ultimately, both sides had to settle for a point apiece, with mid-table Reims undoubtedly the happier of the two with the outcome, while Lens remain in the drop zone and will rue their missed opportunities.