Guy free to join Cumbrians
Hamburg's attacking midfielder Rafael van der Vaart admits he is not living up to his own expectations and wants to score more goals next season.
The Dutchman's arrival last August sparked an upturn in the northern club's fortunes after they had made one of the worst starts to a Bundesliga season in their history.
He only found the back of the net five times, however, as Hamburg's up-and-down season saw them miss out on a place in Europe.
And Van der Vaart would prefer there to be more ups than downs next season, starting with his own performances.
"I can understand everybody who is not happy with me because I'm not happy either," he told Bild.
"I need to play better and I would like to score more than 10 goals next season."
The 30-year-old was made Hamburg's captain during last season and coach Thorsten Fink hopes he will do more to repay the faith shown in him.
"As soon as he arrived, he had such an amazing impact on the whole club, spreading positive energy, but then he struggled after his injury break," Fink told Kicker magazine.
"Once he was made captain, he became stronger again. Overall, he really helped us, but I expect him to do even more in his second year."
Cumbria-born Guy had been told he was free to find a new club and had been training with Carlisle before reaching agreement with Saints to end his contract a year before it was due to expire.
A St Mirren club statement read: "It has been confirmed (on Friday) morning that Lewis Guy has cancelled his contract with St Mirren Football Club by mutual consent."
The 27-year-old joined St Mirren a year ago from MK Dons and hit six goals in 35 appearances.
His final appearance, in a goalless draw with Aberdeen in the penultimate match of the season, saw him substituted 16 minutes after coming on, following an exchange of words with assistant manager Tommy Craig.
Guy, who made over 160 appearances for Doncaster during a five-year spell there prior to joining MK Dons, could be involved in the Cumbrians' forthcoming friendlies.