THE Scarlets were left to rue another false start as they fell to a fourth successive Heineken Cup pool defeat at Sandy Park
The West Wales region found themselves 17-3 down early in the first half only to produce a stirring comeback to level at 20-20.
However, a penalty from Chiefs fly-half Gareth Steenson and a late try from home skipper James Scaysbrook sealed back-to-back victories for the Aviva Premiership side.
The Scarlets clearly hadn't learnt the lessons of their loss at Parc y Scarlets a week earlier as they conceded a try inside four minutes.
A slick line-out move saw Jack Nowell come off his wing, he fed centre Ian Whitten and the former Ulsterman had the gas to fend off the challenge of scrum-half Aled Davies and touch down under the posts.
Steenson converted then made it 10-0 as the Scarlets found themselves reduced to 14 men as full-back Liam Williams was shown yellow for a rash high challenge on No. 8 Tom Johnson.
Aled Thomas, wearing the No. 10 jersey in place of the injured Rhys Priestland, pulled a penalty back for the Scarlets, but it got worse quickly.
Deep inside his own 22, Thomas saw his kick charged down by Johnson and hooker Simon Alcott was on hand to pick up and touch down.
Steenson landed the extras and already the Scarlets were staring down the barrel of another demoralising European setback.
However, Chiefs lock James Hanks was sin-binned for lashing out at Jon Davies off the ball and the visitors started to move up the gears.
Thomas landed a second penalty, then the Welsh side finally turned pressure into points.
Thomas cut through to set up an attacking platform and after some patient build-up by the forwards, hooker Ken Owens burst through a tackle to dive over.
With the conversion added the Scarlets were back in the contest, only for Steenson to give his side a seven-point cushion at the interval with the final kick of the half.
The Scarlets flew out of the blocks at the start of the second half and were level within four minutes.
George North burst onto a pass in midfield, took two or three defenders with him before off-loading to fellow international Scott Williams, who showed a good turn of pace to go outside the last defender and touch down in the corner.
Thomas's conversion made it 20-20, but a concerted period of Exeter pressure eventually led to a close-range Steenson penalty and the home win was completed when man of the match Scaysbrook powered over from close range.