The visitors drew first blood, with points from sharp-shooting forwards John Connellan and Shane Dempsey, who between them accounted for seven points as they led by 0-9 to 0-6 at half-time.
Wicklow lined out with a new look team, with just one player from county champions Rathnew, Ross O’Brien, who picked up a black card 24 minutes into second half.
Wicklow drew level five minutes into the second half at 0-9 each with points from Paddy Byrne, Anthony McLoughlin and Cathal Fitzgerald. But Westmeath had the stand-out player in midfielder Paul Sharry who ensured his team kept the pressure on the hosts.
Connellan put Westmeath back in front with two points and effectively sealed victory in the 50 minute when he hammered home the decisive goal.
J Connellan 1-6, S Dempsey 0-4, P Sharry 0-2, G Egan and C McCormack 0-1 each.
R Finn 0-5, P Byrne and A McLoughlin 0-2 each, D Healy, D Hayden C Murphy, C Fitzgerald 0-1 each.
D Quinn, J Gonoud, F Boyle, J Donohoe, D Lynch, A Stone, J Dolan S Mangan, P Sharry, R Foley, G Egan, J Boyce, S Dempsey, C McCormack, J Connellan.
W Hender Phillips, C Hyland, R O’Brien, A Murphy, D Healy, P McLoughlin, C Murphy, R Finn, A McLoughlin, D Hayden, S Kelly, J Crowe, P Byrne, P Cunningham, C Fitzgerald.
C Davis for C Fitzgerald, C French for R O’Brien (b/c), N Gaffney for P Byrne.
B Tiernan, Dublin.