Steenson slotted over a penalty after 80 minutes to ensure the two sides were locked at 20-20 at the end of normal time in a thrilling final on Saturday.
The long-serving fly-half then came up with the decisive kick with time running out to make last year’s runners-up champions of England just seven years after they were promoted to the top flight for the first time.
Wasps finished the regular season at the top of the table on points difference ahead of the Chiefs and they played out a 35-35 draw in February, but it was the Devon club who edged an epic showdown in the London sun.
— Premiership Rugby (@premrugby) May 27, 2017
Dai Young’s men were a different side in the second half, Elliot Daly going over just a few minutes after the interval and Gopperth converting and adding a penalty to put them 20-14 to the good.
Steenson cut the gap to three points from the tee and Exeter turned down a simple chance at goal which would have brought them level before the fly-half landed a penalty in the 80th minute to keep the Chiefs in it and had the final say in extra time.
Exeter wing Nowell struck first, two days before he jets off on the British and Irish Lions tour, bursting through a gap after taking a pass from Luke Cowan-Dickie at the back off a lineout to scoot over for a try 14 minutes in.
Baxter’s side had the bit between their teeth and Ollie Devoto broke free before conjuring up a superb offload for Dollman to go over for a score, Steenson converting for the second time either side of a Gopperth penalty.
The Chiefs bossed the set-piece in the first half and Wasps, missing the influential Kurtley Beale, looked nervy, but the Coventry-based side were given a huge lift when Gopperth rounded off a slick move and added the extras just before the break.
Wasps came out firing on all cylinders in the second half and Daly got on the end of a kick and chase from Christian Wade which bounced kindly for the Lions man after Nathan Hughes turned over a loose ball
Steenson cut the gap to three points and ensured there would be another 20 minutes with another penalty right at the end, after the Chiefs made the bold move to go for a scrum close to the line rather than go for the posts.
Exeter thought they had won it five minutes from the end of extra time but the TMO saw no evidence that the ball had been grounded. Yet there was still time for Steenson to settle it after Wasps were penalised when a scrum went down.
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