Sullivan holed a 30-foot birdie putt at the last for a six under par 66 and a 12 under total, one stroke clear of Argentine Emiliano Grillo, who had a superb 64, and three ahead of American Patrick Reed, whose 65 propelled him into the mix for the second week running.
The 28 year old won twice in South Africa earlier in the year before bagging a third title at last month’s Portugal Masters, and he delighted the large band of supporters who have travelled from his home town of Nuneaton.
The tournament’s thrilling sub-plot of just who might take the overall Race to Dubai riches also continued to unfold, with Rory McIlroy carding a second consecutive 68 to move into a share of fourth place, two strokes ahead of Danny Willett, over whom he currently has a marginal lead atop the Race to Dubai.
McIlroy is looking to end the season as European Number One for the third time in four years, although third-placed Justin Rose could also yet have a say in proceedings, the Englishman moving to tied seventh on seven under par with a 66.
“It’s been incredible all day with the crowd and the putts going in,” said Sullivan. “I’d missed a couple of short ones on the back nine though so I thought if I could hole the one on the last it would be great. It was a big swing left to right and just dropped in at the front; it was awesome.
“I’ve got 30 mates here and they’re probably a key part in me playing well because they just keep going. Even when you start hitting a few wayward shots, the adrenaline gets going and it’s absolutely fantastic. They’ve been out six or seven times this year and every time I’ve played well.
“It’s incredible to be leading after halfway in such a massive event. A lot of good guys will be chasing me over the weekend and I’m sure they are going to come at me, so I’ve just got to try to do what I did today.”
McIlroy was trying to keep a lid on the expectations given what he could potentially win this week both in terms of this week’s title, the money race and the associated riches.
“I’m treating it like a normal event because I’m just here to win and I know if I win, then everything else will take care of itself. It played a little tricky out there with the wind conditions today and it caught me out a couple of times. Eight under par is a good position going into the weekend and not too far off the lead. I’m happy with my couple of days’ work.”
Leading Australian, Marcus Fraser, was unable to capitalise on his opening round of 66 and is now in a share of 13th position after his round of 72 today while Scott Hend bounced back from a horror opening round of 77 with 69 today but is still well back in the 60 player field
Leading Round 2 scores
132 A Sullivan (Eng) 66 66,
133 E Grillo (Arg) 69 64,
135 P Reed (USA) 70 65,
136 R McIlroy (Nir) 68 68, T Jaidee (Tha) 69 67, C Schwartzel (RSA) 71 65,
137 M Fitzpatrick (Eng) 68 69, J Rose (Eng) 71 66, M Kaymer (Ger) 66 71, B Grace (RSA) 68 69, B Wiesberger (Aut) 72 65, A Noren (Swe) 71 66,
138 C Wood (Eng) 68 70, T Hatton (Eng) 69 69, T Pieters (Bel) 69 69, F Molinari (Ita) 67 71, K Aphibarnrat (Tha) 73 65, B An (Kor) 70 68, M Fraser (Aus) 66 72, D Willett (Eng) 68 70,
139 V Dubuisson (Fra) 72 67, A Cañizares (Esp) 68 71,
140 I Poulter (Eng) 66 74, L Bjerregaard (Den) 69 71, P Uihlein (USA) 71 69, M Warren (Sco) 72 68, A Lahiri (Ind) 73 67,
141 L Westwood (Eng) 71 70, S Kjeldsen (Den) 71 70, A Wall (Eng) 71 70, J Luiten (Ned) 69 72, G Stal (Fra) 71 70, L Donald (Eng) 69 72, P Larrazábal (Esp) 69 72, J Donaldson (Wal) 70 71, L Oosthuizen (RSA) 73 68, F Zanotti (Par) 68 73, R Ramsay (Sco) 71 70, G Bourdy (Fra) 73 68,
142 J Van Zyl (RSA) 72 70, M Kieffer (Ger) 71 71, M Jiménez (Esp) 68 74, R Fisher (Eng) 69 73,
143 K Broberg (Swe) 70 73, E Pepperell (Eng) 71 72,
144 R Karlberg (Swe) 72 72, T Olesen (Den) 70 74, J Quesne (Fra) 73 71, J Morrison (Eng) 71 73,
145 A Levy (Fra) 74 71, R Jacquelin (Fra) 76 69, G Storm (Eng) 73 72, S Gallacher (Sco) 73 72, S Lowry (Irl) 75 70,
146 H Stenson (Swe) 77 69, R Cabrera-Bello (Esp) 76 70, S Hend (Aus) 77 69,
47 L Slattery (Eng) 76 71,
148 D Howell (Eng) 72 76,
149 T Fleetwood (Eng) 77 72,
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