Moeen Ali said he owed England a big score after his Test-best 155 not out helped put Alastair Cook's men in sight of a series-clinching win over Sri Lanka on Saturday.

Ali's innings was at the heart of England's commanding 498 for nine declared on the second day of the second Test at the Riverside.

The Worcestershire all-rounder shared valuable partnerships of 92 for the seventh wicket and 72 for the ninth with pacemen Chris Woakes and Steven Finn respectively.

But both Ali (on 36) and Woakes (eight) were dropped in the midst of an awful Sri Lanka fielding effort.

That was compounded by their third collapse in as many innings this series, as Sri Lanka slumped to 91 for eight at stumps -- a colossal 407 runs behind on first innings -- with Woakes taking three wickets for nine runs in seven overs.

England, who won last week's first Test of a three-match series by an innings and 88 runs at Headingley, are now looking at another crushing victory.

This match saw the 28-year-old promoted to No.7 in the absence of injured all-rounder Ben Stokes.

And Ali was delighted to seize his chance in the middle by scoring just his second century in his 25-Test career following his unbeaten 108 against Sri Lanka in a losing cause at Headingley two years ago.

"I think it's about time as I felt like I owe the team some runs," Ali told Sky Sports.