Toulouse flyhalf Luke McAlister has warned that the French giants will only get better after ending Harlequins' sensational 14-match unbeaten start to the season at Twickenham Stoop last week.

The European Cup showdown between the pacesetters in the English and French domestic tournaments saw Toulouse move four points clear at the top of Pool Six with the return leg in the intimidating and raucous atmosphere of Le Stadium to follow on Sunday afternoon.

McAlister made no secret of the fact that the victory in London was a big boost for his team, who will look to kick on and top the pool from here.

"This was a big one for us – Harlequins were on a bit of a roll with 14 from 14 so to knock them off was big for us," he said. "Our forwards gave us some good ball to work with, and we were very lucky in that regard, and that enabled us to score two good tries.

"However, it is going to be difficult next week when they come to our ground because they are going to be putting it all in so this week we have to concentrate on our physicality because Harlequins are a very physical side so we have to turn up on Sunday and do the job," added the former All Black.

The Toulouse playmaker admitted that his side will be under pressure to perform in front of their home crowd and added that it will be a big challenge to overcome what will be a determined Harlequins outfit out for revenge.

He sid: "We all know we have to win at home so we have a really big game this weekend. But we also know that Gloucester came over and nearly beat us at home so while it is going to be difficult against Harlequins we are looking forward to the challenge.

"Harlequins are good at building phases so it was a big deal for us to front up to them because they physically dominate a lot of teams in the Premiership."

McAlister and Wallaby scrumhalf Luke Burgess are a new antipodean international halfback partnership with the four times European Cup champions and after just three games together the signs are becoming ominous for the rest.

"I am new to the club so the Toulouse history is all sort of new to me and although they have done well in the past, that is for sure, this is a new team and with a lot of guys coming back from the World Cup we are still integrating everyone into the side," said McAlister.

"But I think we are now starting to hit our straps and, although it took us a few weeks to get going, we played well against Toulon before the Harlequins game and the confidence is growing.

"We need to keep building as a team and with a new combination at 9/10 with Luke Burgess and myself – we had not played together before and this was only our third game together – it is going to take time," he said.