Richie Gray's stoppage-time try saw Glasgow Warriors upstage Bath and World Cup winner Stephen Donald with a stunning 26-21 Heineken Cup Pool Three win at Firhill.
Tom Heathcote kicked six penalties before being replaced with 11 minutes to go by Donald, the New Zealand fly-half who was making his Bath debut and his first appearance since lifting the World Cup three weeks earlier.
Donald kicked a last-minute penalty to put his side 21-19 ahead but then Gray, who last week announced he will be leaving Glasgow for Sale Sharks at the end of the season, scored a shock try.
Duncan Weir's attempted drop goal was charged down but Glasgow somehow stole the ball back behind enemy lines and it was all 6ft 10in and 20st second-row Gray who raced through to touch down under the posts.
Weir converted to take his personal tally to 16, while full-back Stuart Hogg also scored a try for the hosts.