Fast bowler Harshal Patel grabbed four wickets and Kamindu Mendis showed his allround skill as Sunrisers Hyderabad upstaged Chennai Super Kings by five wickets in Chennai on Friday.

Patel grabbed 4-28 and was ably assisted by skipper Pat Cummins and Jaydev Unadkat -- both finishing with identical figures of 2-21 -- to dismiss the home team for a below-par 154 in 19.5 overs.

South African youngster Dewald Brevis was the top scorer for the Kings with a blistering 25-ball 42, cracking four sixes and a boundary on his debut for the franchise.

Skipper M.S. Dhoni failed to make his 400th T20 a memorable occasion, managing just six runs and coming out on the losing side.

Sunrisers achieved the target in 18.4 overs for the loss of five wickets with Ishan Kishan leading the way with a solid 34-ball 44 with five boundaries and a six.

Mendis struck an unbeaten 32 off 22 balls, adding 49 in an unbroken sixth wicket stand with Nitish Kumar Reddy who finished with a 13-ball 19 not out.

The victory lifted Sunrisers to eighth on the 10-team table topped by Gujrat Titans with 12 points in eight matches while five-time champions Kings are at the bottom with four points in nine.

Patel, declared man-of-the-match, attributed discipline as the key for his fine bowling.

"I figured out pretty early that hitting it on a good length around the stumps was important because it was hard to hit with the horizontal bat," said Patel.

Dhoni blamed losing a cluster of wickets for the poor batting show.

"I think we kept losing wickets and another thing is in the first innings the wicket was slightly better," said Dhoni. "A total of 157 wasn't a justifiable score."

Earlier, Chennai Super Kings were rocked by Sunrisers's pacer Patel who ripped through the middle and lower-order batting.

The home team started on a wrong note when opener Shaik Rasheed was caught in the slip off the very first delivery of the match by fast bowler Mohammad Shami.

Seventee-year-old Ayush Mhatre was impressive in his 19-ball 30, which was studded with six boundaries, while Ravindra Jadeja managed 21 with a six and a boundary.

Jadeja's dismissal brought Dhoni to the crease as the crowd roared to welcome their hero in his 400th T20 match but Dhoni's stay lasted for just ten balls.

It was Brevis who assured Kings get past 150 with some lusty hitting.

Deepak Hooda also chipped in with a 21-ball 22 with a six and a boundary.