Munich - Germany's Martin Kaymer boosted hopes of a first victory this season despite battling an upset stomach on day two of the 25th anniversary BMW International Open in Munich.
Kaymer, 28, struggled to be one over par after 14 holes before he birdied two of his closing three holes in a one under par 71 and moved to nine under par on the Munchen Eichenried course where he won in 2008.
The current World No. 35, who also has not won on the European Tour in two years, trails one stroke behind the clubhouse leading duo of Austrian Bernd Weisberger (68) and defending champion, Danny Willett (65).
Kaymer's opening round of 64 was his lowest on either of the main tour's in 15 months while his last win was in capturing last December's Nedbank Golf Challenge in South Africa, and an event that will from later this year be co-sanctioned with the European Tour.
"Golf-wise, it was not the greatest day as I felt so bad on the first nine," he said.
"You could see me running back into the clubhouse after my putt at my ninth hole.
"But overall, I am playing well but just not feeling very well."
In fact, Kaymer had been vomiting ahead of teeing off when he was also suffering a bout of diarrhoea. His brother also was seen to deliver tablets to him during the round.
Willett arrived in Munich declaring himself only to be around 60 to 70% fit as he struggled with a niggling back injury.
The England golfer has not competed since withdrawing after the first round of last month's Nordea Masters.
Willett was then observed flat out on the floor of the locker room undergoing treatment following Thursday's round of 69.
He then came out on day two to birdie seven of his first dozen holes before ending with six straight pars.
"Yesterday was a bit hit and miss, and a little shaky given I haven't played a lot of tournament golf in the last 14 weeks, so it was a bit rusty," he said.
"But today I hit some proper golf shots again and I played really nicely."
Wiesberger faced an eagle putt at his last hole and with the birdie putting the 27-year old Vienna-born player in good position for a third Tour victory after winning twice last year.
Visiting American Dustin Johnson played alongside Kaymer to also shoot a 71 and move to seven under par.
"I just struggled with the putter today and really only made one putt and that was a 10-footer on nine," said Johnson.
"I'm only lying three behind at this stage but I just have to get that ball in the hole in a lot less shots than I was taking today."
First round leader, Ernie Els is among the afternoon half of the field contesting the European Tour event.