Partick booked their place in the third round of the CIS Insurance Cup after a dramatic 5-4 penalty shoot out victory against St Johnstone at Firhill.
Following a goalless 120 minutes, Saints' Derek McInnes missed the crucial spot-kick in sudden death.
Paul Di Giacomo passed up two golden opportunities in the first half for the hosts, and Saints almost took the lead in the 24th minute through Kevin Moon.
The deadlock spanned extra-time but the Jags held their nerve in the shoot-out.
Partick: Tuffey, Storey, Twaddle, McStay (Chaplain 107), Harkins, Archibald, Strachan (Connor 54), Rowson, Buchanan, Di Giacomo (Keegan 67), Murray. Subs Not Used: Hinchcliffe, McKinlay.
St Johnstone: Main, Irvine, Stanic, McManus, Anderson, Moon (MacDonald 57), Weatherston (McCluskey 105), McInnes, Stewart (Jackson 62), Hardie, Sheerin. Subs Not Used: Lawrie, Cuthbert.
Ref: M McCurry