Exeter Chiefs recorded their first ever win over Leicester Tigers in an end-to-end game at Welford Park.
Leicester were missing 11 players on World Cup duty and were uncharacteristically error-prone in defence from the off.
The game started frenetically, and both sides had been over by the fourth minute thanks to tries from Chiefs' Sireli Naqelevuki and Tigers' Thomas Waldrom.
Niall Morris put the home side ahead but Tom Johnson's score and eight points from Ignacio Mieres gave Exeter the lead.
Matt Jess crossed for the Chiefs after the break, before a second try for Morris.
George Ford missed two late drop-goals for the Tigers as the visitors held on for victory.
The result is Leicester's third consecutive opening-day defeat.