Pablo Larrazabal shot the round of the day in Cologne by carding a nine-under-par 63 to move into a four-way tie for lead at the BMW International Open.
The Spaniard made nine birdies, including five in a row on the back nine, and went bogey-free on his second round to move level with the overnight leaders on 12-under.
Playing partners Rafa Cabrera-Bello and Danny Willett, the Englishman who won this event in 2012, are also sitting pretty at the top of the leaderboard after 36 holes, as is Argentine Emiliano Grillo.
US Open Martin Kaymer missed the cut on home soil on his first outing since winning his second Grand Slam at Pinehurst, but world number two Henrik Stenson is in for the weekend, four shots adrift of the frontrunners.
Larrazabal is another past winner of the event, having triumphed in 2011 after a playoff with Sergio Garcia.