As I said before, there is little between them. Gayle 9 centuries and 28 fifties in 113 ODIs v Fleming 6 centuries 38 fifties in 235 ODIS (not all as an opener ) - very little between them even as opener .
However when you analyse Fleming's stats as an opener - things look pretty bad for Fleming !!
Mat I NO Runs HS1 HS2 HS3 Ave 100 50 0
unfiltered 235 226 19 6648 134* 116* 115* 32.11 6 38 10
filtered (V Australia as opener) 13 13 0 273 48 40 37 21.00 0 0 1
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Runs Pos Dismissal I *+ R Match
12 1 lbw 2 * L ICC KO 4 v Aus in SL 2002/03 at Colombo (SSC) [1877]
48 2 caught wk 2 * L World Cup Su v Aus in SA 2002/03 at Port Elizabeth [1986]
2 2 caught wk 1 * L TVS (Ind) 3 v Aus in Ind 2003/04 at Faridabad [2053]
40 2 caught 1 * L TVS (Ind) 5 v Aus in Ind 2003/04 at Poona [2055]
29 2 caught 2 * L TVS (Ind) 7 v Aus in Ind 2003/04 at Guwahati [2058]
29 1 caught 1 * L ICC KO 9 v Aus in Eng 2004 at The Oval [2176]
0 1 lbw 2 * W CH Trophy 1 v Aus in Aus 2004/05 at Melbourne (Docklands (d/n) [2196]
34 1 lbw 2 * L CH Trophy 2 v Aus in Aus 2004/05 at Sydney (d/n) [2198]
5 1 lbw 2 * L 1st ODI v Aus in NZ 2004/05 at Wellington (WS) (d/n) [2227]
1 1 caught wk 2 * L 2nd ODI v Aus in NZ 2004/05 at Christchurch (d/n) [2228]
1 1 bowled 2 * L 3rd ODI v Aus in NZ 2004/05 at Auckland (d/n) [2230]
37 1 caught 1 * L 4th ODI v Aus in NZ 2004/05 at Wellington [2232]
35 2 caught wk 2 * L 5th ODI v Aus in NZ 2004/05 at Napier [2234]
As you can see above his performance as an opener (these are the only games where he opened ) against Australia is pretty bad. And looking at these Stats above Gayle's stats look heaps better.