DOHA: Jo-Wilfried Tsonga set up a potential semi-final against Roger Federer after an untroubled 6-2 6-1 win over Spanish left-hander Albert Ramos in the Qatar Open on Thursday.

World number three Federer is seeking a 20th straight victory in his quarter-final against Andreas Seppi.

"It's difficult to play against him (Federer)," the Frenchman said in a court-side interview. "I have to be perfect and play my best tennis but I know I can do it."

Tsonga started strongly against Ramos, breaking the 23-year-old in the opening game.

Ramos hugged the baseline, but Tsonga tempted him to the net with a sliced dropshot the Spaniard could not counter, giving the Frenchman a break chance.

Ramos saved this and another as Tsonga shanked a backhand passing shot into the net, but the world number six broke at the third attempt following a Ramos error.

Tsonga then held to serve to love in his first two service games, taking a 3-1 lead.

Following his second-round win on Wednesday, Tsonga said he was trying to come to the net more. However, this tactic was in little evidence in the opening stages of Thursday's encounter and his first notable foray forward ending in failure as he scuffed his shot into the net.

Ramos, ranked a career-high 66th in the world, seemed to overcome his early service loss, but Tsonga then upped the tempo, hitting a series of bruising ground strokes the Spaniard could only parry as Tsonga eventually put away a forehand winner deep to the right of his opponent and for another break point.

The Spaniard then came to the net, hitting a short stop volley which a groaning Tsonga dispatched cross court for a second break and a 5-2 lead.

Tsonga surged 40-0 ahead for three set points. He blew the first, racing to the net to hit a forehand volley that went long, but won it at the second attempt with a blistering serve Ramos could not return.

With the first set in the bag, Tsonga was more expansive, advancing to the net to hit a range of backhand, forehand and smash winners.

Under pressure Ramos made further mistakes. A long backhand put him a break point down, an error he compounded when he missed an easy put-away at the net to give Tsonga the game and a 2-1 lead in the second set.

Tsonga survived a scare in the next game, saving three break points and then wrapped up the game swiftly as Ramos faded.