WASHINGTON - Two-time defending world champion Marc Marquez is about to find out if he can win the MotoGP Grand Prix of the Americas from something other than the pole position.

The 25-year-old Spaniard led qualifying for the sixth year in a row Saturday on the 20-corner circuit in Austin, Texas, but was denied a sixth consecutive pole position after race stewards imposed a three-place grid penalty. Marquez, a six-time world champion across all categories, won his first series title at the 2013 race and has not lost at the track, winning five races in a row.

Marquez had a fast lap of 2mins 3.658secs ahead of Sunday's third race of the season, bouncing back quickly after a crash to do so on his secondary Honda. But then came the bad news, stewards announcing the penalty for "slow riding on the racing line and disturbing another rider" to drop Marquez to fourth on the grid Sunday. That left him starting on the inside of row two next to Italy's Valentino Rossi, who battled Marquez two weeks ago at the Argentina Grand Prix. Marquez was issued a 30-second penalty for clashing with Rossi on a risky passing move, the Italian later saying he was "scared" to have Marquez on the grid, saying he is a safety risk to other riders.

Spain's Maverick Vinales, who placed second in qualifying and will move up into the pole position, came across a slower-moving Marquez on the first fast lap of his second run and Vinales was forced to abandon his lap, causing the violation.

Marquez apologized to Vinales for slowing him, saying he was concerned about Italy's Andrea Iannone in front of him. "Qualifying was a bit hectic. I crashed and had to take my second bike for the second run," Marquez said. "I went out, and unfortunately I didn't expect Maverick to arrive behind me because I was focused on Andrea, who was waiting ahead and who I knew could be very fast.

"I apologized to Maverick but I didn't realize he was behind me until I heard his engine. So tomorrow I'll start from fourth." Marquez said tire choice and conditions will be critical. "We've worked a lot on used tires and I was able to be consistent during the practices, but this track is quite physically demanding and the temperature should be higher, so we'll see," he said. "We'll try and remain fully concentrated."

Vinales will now start from the pole on his Yamaha after qualifying in 2:04.064. Iannone was third, .551 of a second behind Marquez on his Suzuki to edge French Yamaha rider Johann Zarco for the last front-row spot by .001 of a second. "It was one of the targets for us to be on the front row," Iannone said. "Tomorrow will be a difficult race. I think it's going to be a difficult battle." Now Iannone will move to the middle of row one with the outside spot taken by Zarco.