The White Ferns beat India by 18 runs in their final warm up match ahead of the ICC World Twenty20.
The White Ferns won the toss and elected to bat but were soon reduced to 31 for three before a 81 run partnership between Watkins and Amy Satterthwaite steadied the innings.
Watkins lashed 60 off 51 with Satterthwaite hitting 34 off 35 balls.
At the end of the innings the White Ferns had taken their total through to 123 for five.
Seamer Rumeli Dhar was India’s best bowler taking two for 12 from her four overs.
India made a terrible start in their pursuit of 124, losing their first nine wickets for 68.
Tailenders Priyanka Roy (28) and Babita Mandlik (13) gave their side some hope by adding 38 for the last wicket, but Roy was out off the last ball of the game as India were rolled for 106.
Medium-pacer Satterthwaite backed up her fine batting by taking 2-13 and a brilliant running catch on the boundary.
Kate Pulford claimed two for 18 with Watkins taking two for 24.
Coach Gary Stead said, "“After a poor start there was a great partnership between Watkins and Satterthwaite that got us to a good total in the end.
"There was a big improvement with our fielding and we took two great catches by Satterthwaite and Watkins.
"The bowlers all bowled aggressively all day and overall it was a step up from the England match yesterday and another good workout for us.”
The White Ferns first ICC World Twenty20 match is against Australia at The County Ground, Taunton on 12 June [UK time].