The first Grand Slam of the year kicks into a different gear as the 2015 Australian Open gets into the second week of action.

It didn't take long for upsets to find their way into the mix as the tournament saw big names fall on the very first day when contenders Ana Ivanovic (losing just over three hours into the tournament), Angelique Kerber, and six other seeds in the women's pool lost their opening matches.

The second round found Maria Sharapova go through a close call, needing to save two match points to move on to the next round. Rafael Nadal was another big name that almost went down in the second round, as he needed to battle back to book his third round ticket with a dramatic five-set win against American qualifier Tim Smyczek.

The third round saw the tournament's biggest upset so far, with unseeded Italian Andreas Seppi shocking Roger Federer in four sets 6-4, 7-6 (7-5), 6-4, 7-6 (7-5).

The upset of a revitalized Federer opens up the field slightly for top contenders Novak Djokovic, Rafael Nadal, and Andy Murray who's bids are still alive going into the Round of 16.

Serena Williams got her revenge from French Open tormentor Grabine Muguruza, overcoming a blazing opening set from the 21-year-old on her way to winning 2-6, 6-3, 6-2 to reach the quarterfinals.

The second week of the Australian Open carries on Monday, with the quarterfinals for both the men's and women's singles slated for Tuesday. The action builds up to the highlighted men's final scheduled for February 1.

The Tennis Channel will continue to broadcast most of the early matches, while ESPN2 will be taking care of the rest of the coverage.

Those looking to catch up on the action online can find every match officially available on WatchESPN, while the 2015 Australian Open website will be providing coverage throughout.