Desperate for a win to keep their play-off chances alive, Saha's 55-ball effort, laced with 11 boundaries and three sixes, help the Kings to the highest total of this IPL season.
Put in to bat, Kings XI were off to a flying start with the new opening duo of Martin Guptill (36 from 18 balls) and Saha putting on 68 runs before being separated by leg-spinner Karn Sharma.
Saha, who was promoted to open the innings after South African Hashim Amla left to join his national side for the upcoming ICC Champions Trophy, complimented the New Zealand big hitter well as the Punjab side raced to 50 off just 24 balls.
Guptill started the innings slamming medium pacer Hardik Pandya for two fours in the very first over and then dispatching Sri Lankan Lasith Malinga for a flat six as the Kiwi right-hander looked set for a big innings.
He then fetched two boundaries off Karn's first over before attempting another slog off the leggie, which got the elevation but failed to go the distance as Hardik latched on to a superb catch to bring the smiles back to the Mumbai crowd.
Saha too joined the party, fending the ball to the boundary thrice in the second over from pacer Mitchell McClenaghan before sending Malinga to the leather hunt twice.
Joined by captain Glenn Maxwell (47 off 21), the second wicket partnership flourished to 63 in no time as the Australian meted out special treatment to Karn and veteran offie Harbhajan Singh, clobbering the spinners for five sixes in consecutive overs.
Such was the onslaught from the Punjab duo that the visitors reached 100 in the eighth over of the innings before pacer Jasprit Bumrah knocked off the Australian's off stump after facing 21 deliveries.
Comfortably placed at 131/2, the stage was set for another Aussie Shaun Marsh (25 off 16) to press the accelerator from the first ball.
Marsh got down to business immediately, clobbering Harbhajan and McClenaghan for two sixes to add 52 runs for the third wicket with Saha, who by now had reached his half century off 31 balls.
In the same over from the Kiwi, Marsh perished in his attempt to clear the boundary when he mistimed one from McClenaghan only for stumper Parthiv Patel to take a clean catch in the point region, as Punjab lost their third wicket at 183.
Mumbai managed to pull back things for a while but could not stop the visitors cross the 200-run mark as the left-right combo of all-rounder Axar Patel (19 not out of 13) and Saha added an unbeaten 47 for the fourth wicket to guide the team to their third highest IPL total.
Brief Scores: Kings XI Punjab 230/3 (Wriddhiman Saha 93 not out, Glenn Maxwell 47, Martin Guptill 36, Jasprit Bumrah 1/24) vs Mumbai Indians.
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