In his first round with Andy Forsyth on the bag, Rock started the Open de Andalucia de Golf by Turkish Airlines with a five under par 65 in Malaga and shares the lead with fellow Englishman Jamie Elson and Swedes Johan Edfors, Oscar Floren and Rikard Karlberg.
The 33 year old said: "I've been playing good but not getting on any run of birdies or building any momentum."
That was the way it seemed to be again when he stood level par with eight holes to play, but then came five birdies for a front nine of 29.
Rock has had three runners-up finishes in his career and even walked away with the winning cheque at the 2009 3 Irish Open because it was amateur Shane Lowry who beat him in a play-off.
Elson was on the same winning Walker Cup team as Graeme McDowell and Luke Donald, but ten years on does not have a full European Tour card and needed a top-ten finish in Sicily to qualify for this week's event.
After turning 30 on Wednesday Elson, whose father Pip was The Sir Henry Cotton Rookie of the Year in 1973, came joint fifth on Monday and on the back of that went to the turn in 30 before adding another birdie at the long 12th.
"My fairways hit stats last year were abysmal and that's why I lost my card, but I went over to the States over Christmas and made some really ground-breaking changes, so I'm delighted," Elson said.
"The first time I had a card was 2004 and perhaps it came a bit early for me. I didn't really know what I was doing."
Edfors is still waiting to add to his three wins during the 2006 season, but four birdies in the last seven holes brought him into the picture.
And afterwards the former Scottish Open champion admitted it was a late decision to play.
"It was a good, solid day - I only missed one green," he said.
"Last year I didn't play well here and was planning to take this week off. Then I decided to come, and it was a good decision. The course is in great shape, and the weather is lovely."
Challenge Tour graduate Floren finished with two birdies, while Karlberg is playing on an invitation despite having earned over €240,000 for third place in the Barclays Singapore Open last November.
The 24 year old's effort did not count towards The Race to Dubai because he was a member of The Challenge Tour and failed to play in the required seven events there.
"Today I started playing well, I felt comfortable, but the putts refused to drop on the front nine," he said. "My caddie told me to be patient, and since that moment I started making putts. I got five birdies on the back nine.
"Last year I finished third in Singapore. I earned quite a lot of money, and I tried to gain a European Tour card. But then I neglected the Challenge Tour. At the end I didn't make it to The European Tour and lost my Challenge Tour card as I didn't play enough events.
"Miguel Ángel heard about it and said it was a shame, so he invited me to play at his tournament in Málaga. My target this week is a top ten finish which will allow me to play next week in Morocco. I must try to keep ploughing away week after week. I will also play some Asian Tour events in Malaysia, China and Korea."
Former Open Championship Paul Lawrie is in the group one behind, while Ryder Cup Captains past and present, Colin Montgomerie and Jose Maria Olazábal, had level par rounds of 70.