"We've had a shot at winning all three races and come up short, whether it's circumstances or bad luck or, today, just a little bit of execution," he added.
As for Busch, he was reasonably happy with fourth place after his early pit lane speeding penalty. "I made a mistake and got us mired back in traffic, but we fought hard and we battled back up through there and continued to fight hard all day long," he said.
"Our car just wasn't as fast as it needed to be today on the long runs," he confirmed. “For about 10 laps, the thing was a rocket ship, and then it started getting so loose you could barely hold on to it, and you try to save those tires and not abuse your stuff and it goes loose, worse. That's something we definitely need to build on and work on.
"It's unfortunate that we're not in victory lane and our team mate is, but it's all good for Joe Gibbs Racing and Toyota," he added.
In sixth place, Carl Edwards led Jimmie Johnson to the line. That meant Johnson retains the lead in the Sprint Cup Series standings after three races in 2013, with but his advantage over reigning champion Keselowski has been trimmed to just five points.
"At the end, I just wish we had a little bit more to go up there and race with those guys," said Johnson of his Las Vegas race. "But it was a solid performance, all in all," he added - and it's such solid outings week-in, week-out over the course of a season that result in titles, as Johnson knows all too well from experience.
Full race results and Sprint Cup Championship standings