LONDON (AFP) - Elena Dementieva hardly broke sweat in Monday's sizzling Wimbledon heat as she cruised into the quarter-finals.

Fourth seed Dementieva, a semi-finalist last year, beat fellow Russian blonde Elena Vesnina 6-1, 6-3 in 70 minutes on Court 2 as temperatures rocketed towards 35 degrees.

Vesnina fended off a set point and took the sixth game on a deuce but there was no stopping the Russian number two on her serve and Dementieva wrapped up the first set inside 29 minutes.

Vesnina, the world 37, put up a better fight of it in the second set, holding Dementieva at 2-2 before losing serve.

But there was no stopping Dementieva, who broke serve again to win the match when her compatriot fired long.

Dementieva, making her 11th Wimbledon appearance, now takes on either France's Virginie Razzano or Italy's Francesca Schiavone for a place in the semi-finals.

Meanwhile, Polish 11th seed Agnieszka Radwanska, a quarter-finalist last year, also went through in straight sets against American teenager Melanie Oudin.

World number 124 Oudin, who had to qualify for the main draw, showed plenty of fight but was eventually overcome 6-4, 7-5.

Wimbledon debutante Oudin, who had salvaged set point on her serve, gifted the first set away when she sent a smash wide.

Radwanska, who knocked out China's Peng Shuai and Li Na in the previous rounds, won the second set with three match points to spare to book a quarter-final berth.

The Pole now faces either defending champion Venus Williams or former world number one Ana Ivanovic.

Five-time champion Williams, the third seed, is bidding to become the first woman to win a hat-trick of Wimbledon singles' titles since Steffi Graf claimed three in a row from 1991 to 1993.

Current world number one Dinara Safina, who has yet to win a Grand Slam title, faces 2006 Wimbledon champion Amelie Mauresmo on Centre Court.

The winner of that match will face either Denmark's ninth seed Caroline Wozniacki or Germany's Sabine Lisicki.

Elsewhere, two-time Wimbledon champion Serena Williams, the second seed, plays Slovakia's Daniela Hantuchova.