John Daly endured a day to forget after carding a three-over-par round of 75 to drop well off the lead as Malaysia's Gavin Green took control in the Czech capital.
Daly shared the lead with Green, Thomas Pieters and Callum Tarren overnight having gone five-under for the day in the first round at Prague's Albatross Golf Resort, but the former British Open and U.S. PGA champion struggled to keep with the pace as storms descended on the course.
Play was delayed by almost 90 minutes when the players were taken off the course due to lightning just two hours into the day but when the players returned, it was Malaysian Green who mastered the tricky conditions to take the clubhouse lead on 12-under-par.
Green surged up the leaderboard after making four birdies in a row.
"It was just an up and down day," he said. "I had a couple of really good holes, good birdies and made some putts but I had a couple of bad decisions that led to a double. Then I didn't get up and down for par on 17 and made bogey there but I kept the card pretty clean after that.
"It's fun to be leader and it's been a while since I've been in this position so I'm going to enjoy it - my dad's on the bag so we're going to have a nice dinner maybe and a good sleep and continue tomorrow."
Ryder Cup hopeful Thomas Pieters and three-time Major winner Padraig Harrington sit two shots further behind alongside Fin Tapio Pulkkanen on 10-under while Scott Jamieson, Peter Hanson and Andrea Pavan all head into Saturday's third round on 8-under.