The 19-year-old Australian Tomic won just four points against the serve in a disastrous first set which he lost 6-0 before falling 6-4 in the second set.
The top seed at the event is Janko Tipsarevic, who will play Martin Fischer in the next round after the Austrian beat local wildcard Sandro Ehrat 6-2 6-4.
At ATP Hamburg second seed and defending champion Gilles Simon had to work hard in his first-round match with Argentina's Carlos Berlocq before winning 4-6 7-6(5) 6-1.
Amongst the other highlights on the day was Nikolay Davydenko's 5-7 6-4 6-0 victory over Jarkko Nieminen.
Davydenko will next play top seed Nicolas Almagro or German Tobias Kamke.
And at ATP Atlanta, fifth seed Kevin Anderson registered a routine 6-4 6-3 win over Paolo Lorenzi to move safely into the second round.
But it was a day to forget for seventh seed Alex Bogomolov Jr as he was ousted by American youngster Jack Sock. The 6-2 4-6 6-4 defeat was Bogomolov's fifth in a row.
Gilles Muller posted his 100th career singles win with a 7-6(5) 6-4 success against Australia's Marinko Matosevic; the Luxembourger will now face second seed and defending champion Mardy Fish, who is looking to win the tournament for a third successive year.