World number one Andre Agassi remained on course for a third Wimbledon final after overcoming gritty German Davis Cup player Lars Burgsmuller in a fine match on Court One.
The veteran American produced an accomplished display to gain a routine 6-3 7-6 6-3 victory and ensure there would be no repeat of last year's second-round exit. Agassi confidently marched through to a last-32 clash with Younes El Aynaoui, the 27th seed from Morocco, who beat Nicolas Massu, of Chile, 7-6 3-6 7-6 6-4.
He only dropped his serve once, that was at the start of the second set.
Defending champion Serena Williams advanced to the third round with her ninth successive straight sets Wimbledon win but for the second year running Els Callens made her fight all the way.
Williams needed a pair of tie-breaks to dismiss the plucky Belgian's challenge at the last 32 stage 12 months ago, and while today's 6-4 6-4 win was not quite as tight, the American walked off Court One knowing she had been in a match.
The American led 4-0 at one point on the second set, but Callens fought back to level, but Williams held her nerve to secure a pace in round three.
Filed by James McMahon
