Many were hoping that Zach Osbourne would move up to the 450 and compete in the premier class when the 2018 AMA Lucas Oil Outdoor National Pro Motocross season kicks off on Saturday, May 19, with the Hangtown Classic in round one of the twelve race series, but the Rockstar Energy Husqvarna rider will remain on the 250 and defend his 2017 championship. Many fans think this makes the 250 series over and done, believing that a more mature and seasoned Osborne, having now won the last three straight 250 titles back-to-back (2017 & 2018 SX and 2017 MX), will crush the field and cruise to a fourth straight championship.

While that is a strong possibility, this year showcases a deep field of seasoned veterans with the speed to mount a serious challenge for Osborne.

The challengers

Last season’s runner-up to Osborne, Jeremy Martin, is a two-time champion of the series (2014 and 2015). He finished third to Osborne in the 250 Supercross East standings two weeks ago and had a strong season throughout. He has the speed and experience to pull off the upset.

Aaron Plessinger has been getting faster every year, and two weeks ago, he broke through to win the 250 Supercross West title. He is ready to ride that momentum into the outdoor season and take on all challengers. He is a tough, fast rider who should be even faster moving forward.

Starts are key. If Plessinger can get out of the gate near the front of the pack on the opening turn, he has the pace to stay there.

Zach Martin, the older brother of Jeremy, was running second in the series standings last year before an injury took him out of contention. He has been a frequent top five finisher the past two years, and has excelled outdoors.

He could be a surprise challenger to push the leaders this year.

Teammates Joey Savatgy and Austin Forkner are also expected to be strong competitors in 2018. Savatgy has been in the title hunt for much of the last three seasons, and was less than one lap away from being Supercross champion in 2016 when Osborne's hard block pass knocked him down and cost him the title.

Savatgy was running top three in MX last season before an injury dropped him to fifth in the final standings. He is sure to be in the mix. His teammate, Forkner, has shown flashes of speed to match the fastest competition, but he has had consistency issues typical of a young rider. If Forkner can settle in and find consistency, he has the speed to stay at the front of the pack.

Injury status

This field could have been even deeper, but unfortunately, injuries will keep several favorites out of the lineup this week, and for some, the entire year.

First among the disappointments is Adam Cianciarulo who will miss the entire season due to a torn ACL. Adam just took second place in the final 250 Supercross West point standings, losing to Aaron Plessinger by a razor thin two point margin in the title chase.

Adam won the final race of the Supercross season in Las Vegas two weeks ago, topping the entire combined field of both East and West 250 riders.

A longtime veteran, Martin Davalos, is also recovering from injuries that will cause him to miss the entire 2018 outdoor season. Others that will be missing when Saturday’s gate drops due to injury include Colt Nichols, Mitchell Oldenburg, Cameron McAdoo, and Jimmy Decotis.

Where to watch

Moto 1 is from 2-4 PM ET. It is available to stream online via the NBC Sports Gold Pass, or you can catch it on MAVTV with your local cable/satellite provider. Moto 2 can also be streamed via NBC’s service, or you can catch it on NBCSN from 8:30-10:30 PM ET through your television provider. Televised times may change, so be sure to check the schedule on the day of the race.