Rising stars Denis Shapovalov and Andrey Rublev tracked different routes in making winning starts to their Australian Open campaigns in Melbourne on Monday.

Young Canadian Shapovalov showcased his exciting skills in an impressive straight sets first-up victory, while Rublev needed five sets to wear down Spanish slugger David Ferrer.

Shapovalov, the 50th-ranked left-hander, reeled off a 6-1, 6-3, 7-6 (7/5) victory over Stefanos Tsitsipas of Greece in just under two hours in his first appearance in Melbourne.

Widely seen as one of the up-and-coming stars in men's tennis, the 18-year-old hammered 33 winners, backing up a strong service game.

The Canadian made his entrance on the big stage in August with a win over Rafael Nadal at home in Montreal, before a run to the US Open last 16.

Another of the so-called "NextGen" brigade, Russian Rublev overcame Spanish veteran Ferrer in five sets to advance to the next round.

Rublev, the 30th seed, won an attritional battle with the doughty back-courter before prevailing 7-5, 6-7 (6/8), 6-2, 6-7 (6/8), 6-2 in 3hr 50min on an outside court to reach the second round for the second straight year.

Rublev, the top-ranked Russian, reached the US Open quarter-finals last year where he lost to eventual champion Nadal after upsetting Grigor Dimitrov en route.

The 20-year-old claimed 13 service breaks and hit 77 winners, 40 of them coming off his strong forehand, but offset by 91 unforced errors.

It was a merited win for Rublev over the tigerish Ferrer, who was an Australian semi-finalist in 2013, the same year he lost to Nadal in the French Open final.