The leaders recorded a 19th straight win and ended their hosts' play-off hopes in the process, after bouncing back from a 10-point half-time deficit.

Anderson admitted he had to shake things up.

"We are not always going to be perfect – and we were a little bit flat," he said.

"We let them play football in the first half and we were lucky to only be 10 points down.

"But I do not think we could be accused of being flat in the second half, and the pressure told."

Anderson elected not to risk Sean Long, who missed out with a minor leg injury.

The Saints coach revealed too he has been having to send out a patched up side for some time.

"We decided not to risk Sean, because it could have made the problem worse," he explained.

"But we have plenty of people that have been playing busted for a few weeks.

"It is not that I have to rest people – it is that players needed a break."

Saints were stunned as the hosts produced a dominant first-half display and appeared set for their third win on the bounce.

Rob Purdham, Scott Hill and Julien Rinaldi all crossed as Quins opened up a 16-6 interval lead. But in an impressive second-half display, the Saints rattled in five tries.

Willie Talau grabbed a brace – and James Graham, Jason Cayless and Ade Gardner all crossed too.

Quins coach Brian McDermott conceded his side were unable to maintain their first half pace.

"Defensively we cracked when they kept at us," he said.

"There was always going to be a point where we would be under pressure, and we didn't cope.

"We got ourselves in a position where we were chasing a game we should not have been chasing.

"You have to score points when you are on top against St Helens, and that often means you will come up with mistakes."

Harlequins RL: Melling, Sharp, Clubb, Howell, Sheriffe, Hill, Orr, Ward, Randall, Haggerty, Temata, Purdham, Paul. Substitutes: Rinaldi, Heckenberg, McCarthy-Scarsbrook, Grayshon.

St Helens: Wellens, Gardner, Gidley, Talau, Meli, Pryce, Eastmond, Cayless, Cunningham, Graham, Gilmour, Wilkin, Flannery. Substitutes: Hargreaves, Fozzard, Roby, Clough. Referee: S Ganson (St Helens).