Edmund, 24, had been 14th in the world and the British number one in January but a poor season has seen him drop to 75th, the third highest ranked Briton.

He had not won since an opening-round win against Australia's Nick Kyrgios in the Rogers Cup in Canada in August.

Edmund will now play 14th seed Diego Schwartzman of Argentina in round two.

The Briton edged the first set, but instantly broke 29-year-old qualifier Berankis in the Lithuanian's first service game of the second set on his way to holding a 5-0 lead.

Berankis, 70th in the world, gained one break back but Edmund got the game he needed to advance into the next phase.

If Edmund beats Schwartzman, then he could meet world number one Novak Djokovic in the last 16.

In the first of the round two matches, Russia's eighth seed Karen Khachanov suffered a surprise 7-6 (7-5) 3-6 7-5 loss to Germany's Jan-Lennard Struff.

Another Russian seed, Daniil Medvedev, the fourth seed, also lost in the last 32 as he was beaten 4-6 6-2 6-4 by France's Jeremy Chardy.

The tournament in France features eight of the top 10 players in the rankings, although world number three Roger Federer withdrew from the event on Sunday.