"We are still definitely in the hunt," Roberts told the Western Mail.
"Obviously three of our last four games are away from home.
"But we really need to target all four games.
"It's going to be very tight. The Ospreys have to play Munster, while Ulster are playing very well. They haven't lost for a number of weeks now.
"It's a huge couple of months for us, the Ospreys and the Scarlets in that hunt for that play-off position.
"Our game in hand, away to the Dragons, promises to be a huge match.
"The play-off system in the Magners adds to a very exciting end to the season, especially as the Welsh teams are out of Europe and it's the sole focus now."
The Welsh region have a game in hand on the teams around them in the race for the play-off's and face Connacht at the Sportsground in their next fixture on Friday April 15.