After going 47 holes without dropping a shot, second-round leader Wallace bogeyed the 12th and ran up a double bogey on the 15th — after his wayward drive hit a spectator on the head — in shooting a 2-under 70. He was level in first place on 14-under 202 overall with Marcus Kinhult (68).
Fleetwood, who is hosting the tournament at Hillside in his home town of Southport in northern England, said he struggled for energy and believes his son Frankie, who had tonsillitis last week, "has given me something."
Still, the world No. 16 holed from 25 feet for an eagle on the 11th and also birdied Nos. 12, 14 and 17 to shoot a 68 and delight the sell-out crowd. Fleetwood was 11 under, three strokes off the lead alongside Robert MacIntyre (68).
"It's not been ideal," Fleetwood said. "It's one of them things, just another challenge. I forgot my paracetamol in the bag so Clare (his wife) had to get me some on the 13th tee and that pretty much saved me on the way in.
"Whatever happens, I'm going to be going out late on the back nine on Sunday and the crowd comes to watch that, which is great." Scotland's Richie Ramsay, seeking his first win for four years, was two shots off the pace after a 71.
Wallace is still in a good position to claim a fifth European Tour title in just two years. "We are in great shape," he said. "It's not about winning it on Saturday. It's about putting yourself in good position, so looking forward to tomorrow now."
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