RELATED: Full practice speeds
Edwards, a two-time winner (2008, 2011) at the 1.5-mile track, turned a lap of 191.980 mph in the No. 99 Roush Fenway Racing Ford. He was slightly ahead of fellow Ford driver Joey Logano, who ran 191.320 mph late in the session in the No. 22 Team Penske entry.
Jimmie Johnson, the six-time series champion who leads the series with four career Las Vegas victories, claimed the third-best lap on the leaderboard at 191.137 mph.
Ricky Stenhouse Jr., Edwards' teammate, clocked the fourth-fastest lap at 190.873, but scraped the outside retaining wall with about 12 minutes left in opening practice. After a quick tape-up repair from his crew, his No. 17 Ford returned to the track with slight damage to the right-rear fender.
Martin Truex Jr. triggered an early interruption of opening practice when his No. 78 Furniture Row Racing Chevy slowed in a cloud of smoke with an apparent broken oil line. The 90-minute session was halted for nearly 10 minutes during the extensive clean-up of the dropped fluid.
Truex, in his first year with the Denver-based team, ranks 35th in the standings after two races.
The top five drivers were faster than Kasey Kahne's two-year-old track qualifying record of 190.456 mph. NASCAR's sixth generation ("Gen-6") race car for its premier series set 19 qualifying records in its debut season of 2013. Drivers didn't get a chance to tackle the track record last year at Las Vegas because Coors Light Pole Qualifying was rained out.
NASCAR Nationwide Series first practice (Full results)
Crafton, the defending champion in the NASCAR Camping World Truck Series, drove the No. 33 Richard Childress Racing Chevrolet to a fast lap of 177.637 mph around the 1.5-mile track. He's scheduled to make just his fourth start in the series, after scoring two top-five finishes in three Nationwide appearances last year.
Kyle Busch, a former Nationwide winner in his hometown of Las Vegas, was second-fastest at 177.521 mph. The driver of the No. 54 Joe Gibbs Racing Toyota will be going for his second straight Nationwide Series victory after prevailing last Saturday in a rain-shortened event at Phoenix International Raceway.
Dylan Kwasniewski, 15th-fastest of the 40 drivers to participate, crashed heavily halfway through the 50-minute session, smacking the outside wall on the exit of Turn 4 in the No. 31 Turner Scott Motorsports Chevrolet.
NASCAR Nationwide Series second practice: (Full results)
It seems as if the rookies owned the final Nationwide practice as rookie Ty Dillon topped the charts in the final practice on Friday for the Boyd Gaming 300.
Dillon, who ran third in the first practice, drove the No. 3 Richard Childress Racing Chevrolet to a fast lap of 179.485 mph.
Another rookie, Chase Elliott, was second-fastest at 178.448 mph.
Kyle Busch experienced a flat tire during practice that sent him into the wall on Turn 4 causing him to result to his back up car for qualifying and the race. Busch was third-fastest in the first practice.