Forres hopes of a third round Scottish Cup tie against Stenhousemuir were dashed as East Kilbride came out on top at Mosset Park.
The visitors scored twice through Craig Hastings in the first 16 minutes, but Craig McGovern pulled one back before the interval to give Mechanics hope.
The Can-Cans fell prey to a late goal from substitute Fraser Johnstone before Dachi Khutsishvili scored a consolation for Forres in added time.
Mechanics’ manager Charlie Rowley said: “We were unlucky to lose the toss as we ended up playing into a low sun and a really strong wind, our back four and goalkeeper had real difficulty seeing the flight of the ball.
“That showed in our performance in the first 20 minutes, our defence was all over the shop and on the back foot as East Kilbride took a 2-0 lead, but we reacted and got our way back into the game.
“Goals change games, had any of our chances gone in there was only going to be one winner, but we have to take chances like that especially in games such as this.”
East Kilbride manager Billy Ogilvie said: “We just about deserved the victory but it was close, Forres came at us after we had the best start possible with two goals in the first 20 minutes.
“Once they were 2-0 down they rolled their sleeves up and really pushed us so we were glad to get the win.”
The visitors struck in the sixth minute when Hastings found space in the box to head home from six yards. Ten minutes later the same player scored again as he rounded central defender Steven Fraser to score with a 14-yard drive.
Craig McGovern gave Forres hope with a diving header from Simon Allan’s corner in the 31st minute, but despite creating chances East Kilbride made it 3-1 in the 86th minute with a superb Fraser Johnstone drive.
Forres kept plugging away and Khutsishvili pulled one back a minute into added time with a shot from the edge of the box, but it was too little, too late.