MELBOURNE (Reuters) - Part-time fashion designer, book-writer and mature-age student, Venus Williams reminded the world she remains pretty good at her regular job by cruising through her opening round match at the Australian Open on Monday.

Williams's business-like 6-3 6-2 drubbing of Italy's Sara Errani was her first tour match in four months after a four-month layoff from a knee injury, her last hit-out a hard-fought semi-final loss to Kim Clijsters at the U.S. Open.

Not that Venus, seeded fourth here, would dare celebrate her sister's absence.

"To be honest, I'm just really focused on getting to the next round, regardless of who's there," she said, wearing a white designer tracksuit and toting a sparkling handbag.

"Obviously, you know, Serena is such a great player that of course any tournament misses her.

"But in terms of me actually being here and trying to win, I just have to focus on getting to the next round till it's all over."

Venus's down-time exploits are as almost as famous as her on-court achievements, and the five-time French Open champion did little wallowing during her recuperation period.

Win or lose, the 30-year-old tends to do it in style, and the fourth seed has delighted fashionistas and tabloids by busting out new dresses at the grand slams.

Her flesh-coloured shorts she wore at last year's tournament caused a minor stir as Internet users debated whether she was actually wearing underwear on the court.

On Sunday, her blue, figure-hugging dress with plunging neckline also caused something of an optical illusion as she raced around the similarly-coloured Plexicushion court.

The flesh-coloured shorts were left in the closet, however.

"The design, it really was an 'Illusion' dress, the illusion when I wear the nude shorts under. But at the last minute I decided not to (wear them).

"You know, it's just about focusing on the dress and not anything else. I mean, I had black shorts under," she clarified quickly.

(Editing by John O'Brien)