Triple Olympic silver medallist Katherine Grainger made it safely through to the semi-final of the World Rowing Championships in Poznan.

Grainger won Olympic silver in the quad in 2000 and the pair in 2004, before moving back to the quad in Beijing.

And in her first World Championship outing in the single scull, the 33-year-old finished second in her heat behind the Czech Republic’s Mirka Knapkova in 7:36.59 minutes.

"The first heat at a World Championships is always tough,” said Grainger. "You haven't raced for a while and it felt like I was testing the waters. Now I need to move on from there.”

Grainger was one of seven British crews to qualify on day one and GB Rowing performance director David Tanner insists there is more to come.

"We can take a lot of confidence from today. We've had some really good wins in the Olympic classes and can look forward to the semi-finals,” said Tanner.