Norwich City's defensive resolve produced its best result of the season against Chelsea – and the statistics back their latest centre-back pairing to continue the good work.

Canaries boss Paul Lambert has used five combinations at the heart of his Premier League back line this term, helped by returns after lengthy injury lay-offs in December from USA hopeful Zak Whitbread and August arrival Dani Ayala.

And since enjoying their first full run out together in the 1-1 draw with Fulham at the end of last year, the pair have looked increasing the part with every passing game.

City's first clean sheet of the campaign came in a resolute performance against Champions League contenders Chelsea on Saturday, an afternoon that reaffirmed Whitbread and Ayala's burgeoning partnership on the pitch.

But Whitbread admitted it is their time off it that has helped.

'We've spent quite a lot of time injured together – there's a lot of lonely days in the treatment room,' smiled the 27-year-old.

'We got to know each other quite well and he is a top lad. We just seem to have a decent understanding, but he has come in and worked ever so hard. For such a young lad, he is brilliant and he has got a massive future.'

Both centre-backs also spent time together as trainees at Liverpool, while Ayala – who reportedly cost the Canaries �750,000 – had tutelage at La Liga outfit Sevilla before originally arriving on Merseyside.

And Whitbread admits his partner's assured nature on the ball is a real benefit.

'He can play football, without a doubt,' added Whitbread. 'He has been at Liverpool and been with the best, so he's had a great upbringing and his confidence is there for all to see.

'And I think it does help me having him alongside. It's always good to know there is an option if you are in trouble. But then even his defending against Chelsea, he put some great headers and challenges in so he was spot on.'

Whitbread and Ayala also saw City's safe passage in the FA Cup with a 4-1 win over Burnley at Carrow Road – however, their five-game run together may be sacrificed by Lambert if he decides on changes for Norwich's fourth round tie at West Brom on Saturday. City have a long Premier League trek to Sunderland four days later.

Russell Martin and Leon Barnett remain City's most regular centre-back pairing this season with an unbroken run from September to the start of December.

Although they conceded an average of two goals over their 10 games together, the run included trips to Manchester United and Liverpool, hosting Arsenal and Norwich's heaviest defeat – 5-1 at Manchester City.

Opening-day starter Ritchie de Laet saw his season-long loan from Manchester United ended earlier this month due to injury, while Barnett last featured in the 18-man squad against Tottenham on December 27.

Elliott Ward, yet to feature since injuring his knee in pre-season, completed 61 minutes on his return in the 3-3 second string draw with Chelsea at Carrow Road on Tuesday night and may feature in Saturday's first team squad.