Nick Kyrgios dedicated his Hopman Cup title to late coach Darren Tandy after powering Australia to victory in Saturday's final against Ukraine at Perth Arena.
Gavrilova, number 36 in the world, defeated the 19th-ranked Elina Svitolina 6-4, 7-6 (8-6) after saving set points in the second-set tie-breaker.
The Pole did not drop a set in her run to the title and her triumph will increase her confidence as she builds towards the Australian Open, after a spectacular end to last season.
Gavrilova could scarcely believe her luck.
Meanwhile Watson, whose win over Lisicki was the third of her career against her former training partner, said she is in the shape of her life heading into 2016. "I'm feeling good", she said.
Murray was content with his performance after losing to Kyrgios in his previous singles match. Less about his antics and more about his tennis this week, the Australian win never looked in doubt as Kyrgios blew his opponent off the court in their first ever meeting. The young German pulled back a break in the eight game of the second set after an error-strewn game by the Scot but Murray recovered to seal on his next service game after a big serve down the middle.
With Australia Green having already won the tie, the mixed doubles match did not take place.
A little levity later in the set -- Kyrgios serve is long, but the ball rebounds off the back wall and hits Murray on the top of the head... The win by the host nation side - who have not won the tournament since 1999 - denied Great Britain a spot in the final.
Elsewhere, Roger Federer overcame a stern challenge from Grigor Dimitrov to reach the semi-finals of the Brisbane International.
Despite Watson's impressive mastery of a football, it may be some time before Watson is able to match Andy Murray for showboating ability.
The Australia Green pairing had been on the cusp of being eliminated from the tournament yesterday when they faced a match point against France'sKenny De Schepper and Caroline Garcia, as a loss would have put the British team through.