Two leading players questioned why there was no ambulance on site after Fabrizio Zanotti was struck on the head by a ball in the KLM Open.
Zanotti was on the 16th fairway at Kennemer Golf Club when he was hit by an errant drive from France's Alexandre Kaleka on the 14th.
According to the European Tour, Zanotti did not lose consciousness and received treatment on the course from a doctor and a paramedic before he was taken to hospital.
The 31-year-old from Paraguay was accompanied by fellow players Felipe Aguilar and Ricardo Gonzalez, who subsequently withdrew from the tournament in Zandvoort, Holland, to stay with their friend.
Zanotti was later discharged from hospital and wrote on Twitter that he would now take a few weeks off, but the incident caused a delay of almost two hours and left Italian pair Edoardo Molinari and Matteo Manassero particularly unhappy.
In reference to the death of caddie Iain McGregor in Madeira earlier this season, Molinari wrote on Twitter: "Seems like @fabrizanotti is ok. How is it possible there is no ambulance on site after what happened in Madeira."
Manassero added on Twitter: "Let's hope now that the second incident will guarantee ambulances on site for everybody's safety."
In a statement tournament director Miguel Vidaor said: "Fabrizio received impeccable medical care and attention from the team of doctors and paramedics who were already on site as part of the tournament and who are fully equipped to deal with any medical emergency.
"They subsequently deemed it necessary for Fabrizio to go to hospital as a precaution for further assessment and we are pleased to report that he has been discharged after receiving the all clear."
KLM Open director Daan Slooter added: "We have worked with The European Tour to upgrade the medical provision at this year's KLM Open.
"Unfortunately, there was not an ambulance on site, as requested by The European Tour, since we took the decision not to have one because the first aid provision on site was capable of dealing with an incident like this, and indeed any other medical emergency.
"The hospitals nearby and the ambulance system in Holland could respond quickly if further assistance was required and indeed the ambulance responded within the parameters of Dutch law.
"In light of what happened with Fabrizio, we now have an ambulance on site for the remainder of the tournament."
Zanotti had started his round from the 10th and was level par after six holes when the incident occurred.
Molinari carded an opening 66 to lie one shot off the lead held by defending champion Joost Luiten and Scotland's Jamie McLeary.
Luiten carded four birdies, an eagle and just one bogey in his 65, while McLeary joined the Dutchman on five under with a birdie on the 16th just before play was suspended for the day.
Play in the first round was scheduled to resume at 8am today.
"It is always nice to shoot a 65," said Luiten, who had downplayed his chances of a repeat victory.
"I played well and didn't make any mistakes. That's the key on this course, keep the ball in play and take your chances. For me it was a good solid round and I hit some nice spots.
"Sometimes you can be conservative and take irons off the tee, but if you feel good with the driver you have to hit it and make a tough hole into a birdie hole.
"It all depends how the winds are, but I was hitting my drive well and I tried to take advantage of that."
Italy's Andrea Pavan and France's Gary Stal were alongside Molinari on four under, with Ryder Cup player Thomas Bjorn and vice-captain Miguel Angel Jimenez off the pace on one over.