Bionic backman Nick Malceski's knee held firm but Sydney teammate Tadhg Kennelly's popped out as the Swans cruised to a 91-point thumping of Essendon today.

Sydney booted 15 goals to three after half-time to storm to a 21.17 (143) to 7.10 (52) victory at ANZ Stadium to send the rebuilding Bombers into freefall with their fifth straight loss of the season.

Michael O'Loughlin enjoyed the flood of ball into the Swans' forward line with six goals to just pip the tireless Brett Kirk for best on ground honours.

Much of the pre-match interest had been on Malceski's return from a revolutionary knee reconstruction three months ago.

The left-footer made a solid return but will be forced to share tomorrow's headlines with Kennelly after the Irishman dislocated his knee.

Kennelly missed nine games all up last year because of knee problems and his absence hindered the Swans at the business end of the 2007 season.

Early on, the Swans looked like turning the first day match at the venue in three years into a picnic, busting out to a 27-point lead at quarter time with the visiting side only managing two points.

Malceski came off the bench and stepped and weaved with confidence through traffic on his repaired knee and provided some useful touches.

But he still has some way to go to be back at his damaging best, failing to get the distance from a 50m set shot and being badly caught out in the back pocket.

The Bombers opened the second term with four straight goals and if that wasn't enough of a problem for the Swans, Kennelly's knee cap then popped out.

The premiership player grimaced with pain and tried to knock it back in before being assisted off the field.

Kennelly made a quick initial return from the same injury last year, only missing two games but the Swans will be keen to ensure the problem doesn't flare up again later in the season.

His run and carry is crucial to the Swans and he was badly missed last season as the Sydney missed the grand final for the first time in three years.

In his absence today, the Swans booted the last two goals of the first half to lead 6.11 (47) to 4.7 (31) at the long break.

The home side cruised out to a 28-point lead following O'Loughlin's brave mark in front of teammate Ryan O'Keefe and Essendon's Henry Slattery.

The Bombers responded and Leroy Jetta tried to lift his teammates with a neat trick, soccering the ball through the legs of two Swans players for a much-needed goal.

However the home side booted five goals in ten minutes to complete the third term before piling on eight unanswered goals in the final quarter.

Sydney plays Port Adelaide at AAMI Stadium on Saturday while the Bombers host Richmond at the MCG.

AAP