And at the end of the day, it was Smitherman and his relegation-threatened Portsmouth colleagues who ended victorious - but only by a nine-run margin. And it was only thanks to some wayward Burridge bowling.
Batting at No 3, Smitherman had to wait for his chance as Richard Warner (38) and Indy Chakrabati (22) put on 77 for the first wicket.
He took it with both hands, though, to reach his second Hampshire League hundred and his first since hitting 115 for the 2nds against New Milton 2nds four years ago.
Smitherman was finally out for 101, after sharing a 140-run stand for the fourth wicket with skipper Matt Shaw (46).
Burridge contributed a stunning 43 wides as part of an overall total of 55 extras as Portsmouth amassed a daunting 318 all out (Stuart Downs 3-45) - the final four wickets falling for just two runs.
In reply, Wickramasinghe lost opening partner Simon Bevis for a duck, but then shared a 93-run second wicket stand with Francis Moore (48).
There followed two more half-century partnerships - 72 for the third wicket with skipper Nick Damley-Jones (22) and 63 for the fourth with Charlie Creal (27).
Simon Creal, batting at No 7, ended on 46 not out but Burridge closed on 308-9 (Henry Woolf 3-50).
It was only Portsmouth’s fourth win in 13 league games and, with four matches left, they remain 15 points adrift of fourth-bottom Alton 2nds - and the bottom three go down.
Rohit Choudhary made a remarkable debut for Bournemouth 2nds against Longparish.
The opener, whose transfer from league rivals Burridge only went through last week, blasted an unbeaten 179 at Chapel Gate with 24 fours and three sixes.
Choudhury, who played for Dorset Indians last summer, dominated the innings as his new side posted 289-4.
Longparish crashed to 37-6 in reply before limping to 110 all out to lose by 179 runs - exactly the same amount Choudhury struck.
Bramshaw opener Tom Arnold moved to the top of the overall Hampshire League run charts with his fourth century of the season.
He struck an unbeaten 109 in a four-wicket win over Tichborne Park to take his seasonal league tally to 927 runs from 12 innings - seven more than Craig Dennett of Suttoners has accrued.