As dress-rehearsals go it was shabby but the Crusaders won't be complaining too loudly - they are once again in the Super Rugby play-offs.

Tonight's 38-24 win over the Western Force in Christchurch encapsulated the Crusaders season; at times they were brilliant as they attacked with gusto and precision and at others they were frustratingly poor as they spilled passes and conceded penalties that thwarted their momentum.

In fact, so sluggish was their second-half effort that they were beaten 21-6 by a Force side that refused to be bowed in the final game played in their colours by veteran lock Nathan Sharpe.

There was even the sight of the Crusaders stand-in captain George Whitelock being yellow carded by referee Glenn Jackson in the 74th minute and without their blindside flanker guarding the short side the Crusaders conceded their third try - a late effort by replacement halfback Josh Holmes.

So now for the play-offs: the win guarantees the Crusaders the top wildcard position - fourth in the standings - and their opponent in next weekend's qualifying final in Christchurch would be determined by how the Bulls and Sharks fared in their games in South Africa tomorrow morning (NZ time).

The Chiefs have already secured top-two placing as the best team in the New Zealand conference and have the bye next week.

Two controversial tries from a television match official - a familiar scenario in recent weeks - had viewers scratching their bonces in the first half and once again the Crusaders were the benefactors.

In their previous match against the Chiefs Andy Ellis was awarded a contentious try when TMO Bryce Lawrence ruled he had scored and last night the nippy halfback got the thumbs-up from Vinnie Munro when he appeared to ground the ball short of the line.

Earlier fullback Israel Dagg also had his heart cockles warmed by the TMO's charity as he appeared to lose the ball in the corner in the opening minute.

In reality, however, nothing was going to prevent the Crusaders from triumphing and at halftime coach Todd Blackadder was so confident he ordered stars Richie McCaw and Dan Carter to bundle themselves in cotton wool.

Blackadder wasn't done, either; within minutes of the re-start tighthead prop Owen Franks and Ellis also put their feet up.

Given his side held a 29-point lead at halftime, Blackadder appeared entitled to take the calculated gamble.

Yet unease would have crept into the coach's box when the Force replied with tries to Kyle Godwin and Alfie Mafi to close the gap to 18-points mid-way through the half.

Even though Holmes grabbed his late effort, it was just cosmetic. The damage had already been done.

Despite giving away a number of penalties in the first spell and being unable to score a try for almost 20 minutes mid-way through the stanza the Crusaders still trotted off to the sheds with a 32-3 halftime lead and the bonus point bagged.

Sean Maitland, who has largely been on the outer since the Crusaders shock loss to the Rebels on May 12, crossed from his right wing to score on the opposite side of the park in a performance noticeable for his higher work-rate and give Blackadder a late poke in the ribs ahead of the play-offs.

It was always going to be difficult to top Matt Todd's try, however.

It began with a strong burst from McCaw near halfway, involved some sweet inter-change passing between several men - including Todd - and finally resulted in the plucky openside flanker diving over.

Yet it will be a worry for the Crusaders they were unable to score a 5-pointer in the second half.

Crusaders 38 (Israel Dagg, Andrew Ellis, Sean Maitland, Matt Todd tries Daniel Carter 3 cons Carter 2, Tom Taylor 2 pens) Western Force 24 (Kyle Godwin, Josh Holmes, Alfie Mafi tries Brett Sheehan 2, Godwin cons Ben Seymour pen) at Christchurch Stadium

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