Padraig Harrington missed the cut at the Indian Open on Friday after carding a two-over 74, while Terry Pilkadaris surged into a three-shot lead.
The three-time major winner finished tied 33rd at the Valspar Championship last week, but his tilt in New Delhi was cut short as he finished one shot below the cut.
Harrington produced a one-under 71 on the opening day and looked set to improve when he made the turn in his second round one shot below par.
However, bogies on holes 11, 12 and 14 proved costly and his quest for a first trophy since the Honda Classic on the PGA Tour in March 2015 goes on.
Australian Pilkadaris produced the best round of the competition and took a three-shot lead by carding an eight-under 64 that included nine birdies.
The world number 313 could have done even better had he not produced a bogey at the final hole, but 13-under over two days puts him in a comfortable position ahead of second-placed pair Nacho Elvira and SSP Chawrasia - a four-time runner-up at this event.
Pilkadaris replaced Im at the summit, the American failing to build on a bogey-free first day with a two-over 74 sending him down to tied 14th.
Lee Slattery produced his first albatross in his 303rd European Tour start on the par-five eighth hole, but it he missed the cut despite being five-under for the day.
But it is Pilkadaris who heads into the weekend in charge, and he is aiming to keep his cool for the remainder.
"I kept giving myself chances and it was nice to take advantage of them. You've got to roll with it and don't try to step out of the way and trip on your own feet. Just keep it simple," he said.