Tiger Woods moved up into the top ten on his return to the Omega Dubai Desert Classic - as Lee Westwood moved into a tie for third.
Resuming on one under par following his first round closing eagle, Woods birdied the 12th, 13th and 18th to reach the turn in a three under 34.
Westwood, meanwhile, birdied the two par fives on the back nine and on five under was only two behind overnight leader Rory McIlroy, one of the second round's later starters.
It was not such a good start for German Martin Kaymer, the third member of the world's top three grouped together for the final leg of The European Tour's Desert Swing.
Kaymer, needing a top-two finish to have a chance of dethroning Westwood, also made four on the 549 yard tenth after hitting the hole with his bunker shot, but then came bogeys at the 14th and short 15th.
That sent him down to two under, but a chip to six feet from over the green at the 18th brought him back to his starting position of three under and he was joint 16th.
McIlroy, meanwhile, had been joined on seven under by South African Thomas Aiken, who birdied the tenth and 15th and had still to card a bogey after 24 holes this week.
Woods added yet another birdie on the second despite driving into the rough, and after a par on the 568 yard next he was in a tie for sixth and only two behind McIlroy, Aiken and also Dane Anders Hansen.
Westwood also birdied the second and shared fourth spot with Ryder Cup team-mate Peter Hanson.
Woods continued his charge with a 25 footer on the short fourth and a wondrous approach to two feet at the 485 yard par four sixth not only brought him his sixth birdie of the day, but took him into a share of top spot.
After five holes of his first round yesterday he was two over and tied for 96th.
Westwood, though, bogeyed the sixth after driving into the rough and slipped back to sixth place on five under.
