Striker Jamie Vardy may have returned to the headlines as Leicester City closed in on the Premier League title, but the contribution by the team's defenders cannot be overlooked.

In the 2-0 victory at Sunderland Vardy became the club's first player to reach 20 top-flight league goals since Gary Lineker's 24 in 1984-5.

Just as significant, however, was the clean sheet kept by goalkeeper Kasper Schmeichel and those in front of him. It was their fifth in succession, the previous four all having earned vital points in 1-0 wins.

Earlier in the season Claudio Ranieri's side were conceding regularly -- including five in a home defeat by Arsenal -- but since the experienced Italian introduced Danny Simpson and Austrian Christian Fuchs at full back, there have been 13 clean sheets in 22 games.

Thanks to that pair and central defenders Robert Huth and Wes Morgan, Schmeichel's fine save from Fabio Borini in the first half at Sunderland was the only time he was tested.

It is now 490 minutes since West Bromwich Albion became the last team to pierce the armour, in a surprise 2-2 draw at Leicester on March 1.

West Ham United, in sixth place and on a good run, are the next team to attempt to find a chink when they visit the King Power Stadium next Sunday.

Swansea City, in 12th place, follow them, by which time Leicester could be in a position to sew up the title.

Their remaining fixtures after that are away to Manchester United and Ranieri's former club Chelsea, either side of a home game with Everton.

Following Manchester United's defeat at Tottenham Hotspur, Leicester have also qualified for the Champions League for the first time.

They have only ever played in European competition three times, the last of them in the 2000-1 UEFA Cup.

"The fans must continue to dream but we must continue to be concentrated and focused," Ranieri told the BBC on Sunday.

"Now we have two tough matches at home. We don't achieve nothing yet."