Joern Pollex/Getty Images
|Daniel Brands def. No. 1 Roger Federer
|Robin Haase def. No. 3 Janko Tipsarevic
|Marcel Granollers def. Federico Delbonis
|Victor Hanescu def. Roberto Bautista Agut
||7-6 (7-2), 3-2, retired
Underdogs ruled on Thursday at the 2013 Swiss Open as top seeds Roger Federer and Janko Tipsarevic both lost in their opening matches, in straight sets no less, per SI.com's Beyond the Baseline on Twitter:
Federer, who won this tournament for the first and only time in 2004, struggled with his serve throughout Thursday's match, managing to put just 52 of his first serves in play. Brands would capitalize by winning 13-of-27 second-serve return points.
Fed, who was playing his first match at this tournament since 2004, was out-aced 11-8 and went 0-for-5 on break-point chances in the stunning defeat at the hands of the world No. 55.
Earlier in the day, third-seeded Serb Janko Tipsarevic was knocked out quickly by Robin Haase. Tipsarevic doubled faulted six times in the match and had his serve broken four times.
In other action, 2011 Swiss Open winner Marcel Granollers defeated Federico Delbonis in straight sets, winning 50 percent of his return points for the match and converting on 5-of-8 break-point opportunities.
2008 Swiss Open champion Victor Hanescu advanced to the quarterfinals as well on Day 4, taking the first set from Roberto Bautista Agut in a tiebreaker before securing a berth in the next round after the Spaniard retired with a back injury while trailing 3-2 in the second frame.
After the first two rounds of the Swiss Open, only four seeded men remain.
With both Federer and Tipsarevic eliminated, 2005 runner-up Stanislas Wawrinka has become the favorite to win his first Swiss Open heading into Friday's quarterfinals.