And a high finish at the spectacular Bro Hof Slott course on Sunday could lift the 29 year old Italian into a top nine spot on Europe's Ryder Cup table alongside his brother Francesco with only five more weeks to go in the race.
Setting off on the back nine in the first group of the day at 7.20am Molinari birdied the long 13th, short 17th and then 407 yard 18th to be three under par and joint leader with Englishman Danny Willett.
Also playing the inward half first Willett, a team-mate of Rory McIlroy in the 2007 Walker Cup, made gains on the 12th, 14th and 15th.
They were one ahead of Willett's compatriot James Morrison, The European Tour rookie who won in Madeira in April and then lost a play-off for the Open de España to Alvaro Quiros, Argentina's Rafa Echenique and Australians Scott Strange and Richard Green.
Molinari was partnering young American star Rickie Fowler, who like Dustin Johnson, KJ Choi and Rory Sabbatini had stayed on after last week's Open Championship.
Fowler, who recovered from an opening 79 at St Andrews to finish in a tie for 14th, also had three birdies in his first nine holes, but there were also three bogeys on his card.
Open Champion Louis Oosthuizen and Johnson, the player who missed out to Graeme McDowell at the US Open Championship last month with a closing 82, were among the later starters.
Molinari went to four under on the long tenth, but he was joined when Morrison started the front nine with further birdies on the first and third and then by Londoner Anthony Wall as well when he had four birdies in five holes.
Swede Jesper Parnevik, playing his first event since February after suffering a career-threatening fractured vertebrae, turned in one under - far better than his pre-tournament prediction.
The former Ryder Cup star did not start practising again until Monday and his first words on seeing the course were: "This could be very embarrassing."
Molinari's first error came on the 239 yard fourth, his 13th, but after bogeying there he made a 15-foot downhill putt on the next and at the short seventh he sank a bunker shot.
At five under, though, he still had company at the top. Left-hander Green had a hat-trick of birdies from the 11th.