Leicester took control of Pool Five in the Heineken Cup as five second-half tries saw them ruthlessly brush aside the Scarlets with a bonus-point win at Welford Road.
The hosts led 13-10 after an absorbing first half thanks to a Martin Castrogiovanni try and eight points from Toby Flood. The Scarlets had grabbed the first try of the game, a lovely score from Morgan Stoddart, with Stephen Jones adding the conversion and a penalty.
But the Welsh side were blown away as Ben Youngs, Thomas Waldrom and Tom Croft went over within 10 minutes of the resumption, with further tries from flanker Croft and centre Matty Smith completing the scoring.
The Scarlets had been feted in some quarters following their enterprising display in their win over Perpignan in their European opener and they had headed to the east Midlands looking to become the first Welsh side to win here in Europe.
But, after a lively opening, they were ground down and suffocated by Leicester's physicality and forward prowess as their scrum and lineout crumbled.
The Welsh region had made a quick start and only a cynical deliberate knock-on by Tigers' wing Alesana Tuilagi prevented Rhys Priestland putting Sean Lamont over down the left, earning the Samoan a yellow card.
The visitors made the extra man count in the 15th minute as Regan King launched a counter-attack from the Scarlets' 22 that saw Lamont race clear. The Scotland wing fed Josh Turnbull, who found King for the centre to deliver the scoring pass to Stoddart for a wonderful try by, converted by Jones.
The lead lasted all of two minutes as Leicester took advantage of a blatant forward pass, missed by referee George Clancy, to send Smith racing down the right. The ball went loose but the Tigers' pack regathered to drive Castrogiovanni over, Flood's conversion levelled the scores.
Flood, returning from a knee injury that had sidelined him since the first day of the season, then missed with a straightforward penalty attempt which would have given Leicester the lead.
The Scarlets somehow survived a period of sustained pressure as Leicester's pack surged over the line but were held up, before the home side failed to make the most of their scrum dominance as the creaking visiting pack held out.
But the west Wales side's defensive effort was taking its toll with a stream of penalties keeping them pinned in their own quarter, and Flood was on target from bang in front of the sticks in the 32nd minute as Leicester took the lead for the first time.
A powerful surge from Tuilagi saw the two-time champions step up the pressure and the inevitable yellow card followed when King became the latest Scarlet to infringe and Flood knocked over his second penalty.
The Welsh side saw Wales prop Rhys Thomas stretchered off with a knee injury, Deacon Manu his replacement, but responded gutsily as Jones trimmed the gap with a penalty seconds before half-time.
But any hopes of an away win were effectively ended when Youngs carved through the Welsh side's defence for a try less than two minutes into the second half which Flood converted.
King returned from the bin but things soon got worse when the visitors went to sleep after conceding a free-kick at a scrum, Youngs took the quick tap and fed Waldrom who simply waltzed through unhindered to score behind the posts, Flood again converted and the lead was out to 27-10.
The bonus point was secured after 51 minutes when captain Geordan Murphy made a half-break after grabbing a poor King pass and offloaded for Croft to rampage over for another converted score.
The Scarlets were in complete disarray and a fifth Leicester try arrived just after the hour mark as Tuilagi pounced on a loose ball in his own 22 and kicked deep into the visitors' territory.
He penned in Lamont in front of his own sticks and the turnover ball was moved wide for Croft to saunter in for his second, again converted by Flood.
The rout was completed when Murphy burst onto a flat pass from replacement Billy Twelvetrees. The full-back was brought down just short but Smith was left with an easy finish.