Australian Bernard Tomic returns to Colombian Alejandro Falla during their match at the Colombian Open in Bogota, Colombia on Wednesday. Photo: IC

Australia's frosty relationship with bad boy Bernard Tomic looks set to thaw after the 21-year-old displayed grit and passion to grind down big-serving Croatian Ivo Karlovic 7-6, 3-6, 7-6 in the Colombian Open final on Sunday.

Too late to win automatic qualification for next month's US Open, Tomic's second ATP title was a timely riposte to an army of critics in his home country and came only days after being dumped by powerful sports management company IMG.

Tomic's victory has lifted his world ranking up to 70 after it had drifted out of the top 100, ending a dreadful six months in which he struggled to string two wins together after coming back from surgery on both hips.

Prior to the surgery, ­Tomic was forced to ­retire in the first round of his home Grand Slam against Rafael Nadal in January and despite his clear discomfort, was jeered by fans at Rod Laver Arena.

He was further slammed by home media in Australia after he bowed out 6-0, 6-1 in his comeback match to Finland's Jarkko Nieminen at the Miami ­Masters, losing in 28 minutes, the quickest ATP victory since records started in 1991.

Once touted a future top-10 player, Australian tennis fans had become increasingly weary of the two-time junior Grand Slam champion who showed immense promise with a Wimbledon quarterfinal appearance at the age of 18 but has since failed to live up to his own lofty expectations.

Tomic's struggles have been magnified by the rapid rise of 19-year-old Nick Kyrgios, who stunned 14-time Grand Slam champion Nadal to also reach the quarterfinals at Wimbledon earlier this month.

Supremely gifted and seen as a humble, wholesome athlete, Kyrgios' Wimbledon breakthrough caused a frenzy down under and inevitably raised comparisons with Tomic.

"At last, we no longer have to pretend we like Bernard Tomic," a News Ltd commentary said before Kyrgios' matchup with Nadal at Wimbledon.

News of Tomic's Bogota win prompted a backhanded compliment from the same media company.

"Bernard Tomic finally did something right," a headline on News Ltd media portal news.com.au read Monday.

Though the victory in a minor tournament in South America may seem a small step in ­Tomic's comeback, footage of the Australian nearly breaking down in tears of frustration ­before collapsing on the court after closing out victory are likely to do much more for his ­damaged brand in Australia.