AUSTIN - World champion Marc Marquez cruised to victory in the Grand Prix of the Americas on Sunday to register his second win in two races this season but he admitted it was a boring triumph. The Spaniard repeated his maiden Texas MotoGP success from 2013 when he also won from pole position. Marquez, who won the season-opener in Qatar last month despite breaking his leg four weeks earlier, finished 4.174sec ahead of Honda teammate Dani Pedrosa with Ducati's Andrea Dovizioso taking third place, a huge 20 seconds off the lead."I am so happy for this victory. The start was good and the 25 points important for the team even if the race was a little boring," said Marquez. In a dramatic start, the 2010 and 2012 world champion Jorge Lorenzo had a jump start from fifth on the grid. The Spaniard had to endure a compulsory ride-through the pit lane on his factory Yamaha at the end of the first lap.At the front, Marquez charged away from the field and was never threatened, keeping Pedrosa in second place. Italy's Andrea Iannone on a Ducati carved his way through the field from ninth place and settled into third in the early stages. Valentino Rossi, on the second factory Yamaha and who was runner-up in Qatar behind Marquez, was fourth at the halfway mark after passing Dovizioso, Stefan Bradl and Cal Crutchlow.But the veteran Italian slipped back down the field as he struggled with grip on his front tyre. Such were his problems that even the satellite Yamaha riders of Aleix Espargaro and Bradley Smith comfortably swept past him. Marquez's lead over Pedrosa had grown to five seconds with four laps to go while Dovizioso, who had started in 10th, was up to third. Rossi was eventually eighth, 45 seconds off the pace, while Lorenzo fought his way back to 10th place. The nine-time world champion earned eight points to give him a total of 28, dropping him to third on the overall standings. "We destroyed the front tyre completely on the right side," Rossi said. "I had the same problem during the weekend. This morning we made a good step and with a used tyre I could do all the warm up so we were quite positive. Unfortunately after seven or eight laps the front was gone. It's a pity ... unfortunately it wasn't to be."Lorenzo pitted early and when he rejoined the race he was in the back of the pack in 23rd. "I wasn't thinking and was distracted and I made a big mistake in the start," said the four-time world champ. "I just tried to push at the maximum afterwards to get the best result but the race was almost over for me." Spain's Maverick Vinales won his first career Moto2 race with a commanding victory. Vinales, the Moto3 world champion last season, stormed from sixth place on the grid under rain-filled skies to take victory by 4.009sec from pole sitter Esteve Rabat.Vinales, riding a Kalex, had finished in fourth spot in Qatar where fellow Spaniard Rabat, also on a Kalex, had triumphed. Dominique Aegerter of Switzerland was third Sunday on a Suter. Australia's Jack Miller won his second successive Moto3 race. The 19-year-old, who captured his maiden race victory in Qatar, had started on pole on his KTM. He then survived a series of challenges from fellow KTM rider Romano Fenati, who was second, and Efren Vazquez on a Honda, on the last two laps to secure victory. "I felt strong on the brakes. That's always been one of my strong points, maybe too strong as it can kill the exit speed," said Queensland native Miller who won by just 0.069sec. "But here it works really well. I'm stoked to have won, I led every lap."