Russell Martin’s Southampton may be left ruing their inability to bring in another centre-forward from almost the first minute of the Premier League season to the last. With Adam Armstrong yet to prove that he can translate his prolific Championship form onto the big stage, and with Cameron Archer missing a penalty in that defeat to Manchester United, a lack of goals already looks like The Saints’ Achilles heel. Still winless thanks to Sam Morsy’s 95th minute equaliser in last weekend’s 1-1 draw with Ipswich Town, no team in the division has scored fewer than Southampton. Their return of two i…