Hyundai are racing this weekend with their two cars decked out in the colours of the Irish flag as they mourn Craig Breen, their Irish driver who died in an April 13th testing crash.
Neuville ended the day 5.7 seconds clear of Toyota's Elfyn Evans (34) with Estonian Ott Tanak (35) third for M-Sport Ford and a further 24.3 seconds adrift on the asphalt roads to the west of Zagreb.
The Belgian took the lead after the second stage when Toyota's Sebastien Ogier (39), who won four of the stages including the opener, lost a minute and a half with a wheel change after hitting a pothole.
Reigning world champion Kalle Rovanpera (22), last year's winner in Croatia, also lost two minutes changing a wheel on his Toyota at the same place.
"We have done a decent job, but it hasn't been easy at all," said Neuville.
"Hopefully we can finish in first place at the end. That would be a great achievement for the team and for us."
