Widely considered the most exciting season in years, the 2017 Monster Energy Supercross series ends on Saturday in Las Vegas with two unregulated Championships up for grabs.

It's been a while since determining the 450 class Champion reached Round 17 but a mid-season surge by Eli Tomac turned a 29 point, fourth-place deficit into a three point lead just two weeks ago. Now, he faces a nine point gap behind the two-time defending Champion Ryan Dungey who is looking for his fourth overall title and has not finished below fourth-place this year.

Last week, Tomac quickly got out front in East Rutherford mimicking nearly every round since Minneapolis by leaving the field and on the way to taking his 10th win and extending his points lead. But unlike all the other blowouts this year, he washed out his front on a turn allowing Dungey and a host of other riders to pass. Also, un-Tomac like is he never recovered as he did several times this year. At one point Tomac perfectly demonstrated how to case a jump and overall looked much like James Stewart did last year - erratic and a bit out of sorts.

Tomac finished eighth while Dungey must have watched reruns of "The Wonder Years" the week prior since he got by with a little help from his friend and took the lead on the last lap after Achates/teammate/training partner Marvin Musquin made a "mistake" which pulled him briefly to the side. Dungey won the race, got an extra three points and can finish in fourth-place on Saturday, even if Tomac crosses the checkers first, to claim the 2017 450 class Supercross Championship. Dungey last finished outside the Top 4, taking sixth-place for Round 16, in 2014. Dungey's stat line for Las Vegas since entering the 450 class in 2010: 1-2-1-2-2-1-1.

Marvin Musquin (25) made his presence felt by Eli Tomac (3) in more ways than one last week

Questions of team tactics were raised; fans were amused, angry or conciliatory but no one doubts Musquin pulled off to give Dungey the lead. However, it was a rough and tumble track and though Dungey led nine laps after Tomac's crash, perhaps it makes a modicum of sense to allow Musquin by and follow him as he carved out lines for the final 12 laps. Probably not Plan A, B or C, but wherever the truth lies, Dungey hasn't enjoyed a lead this large since the seven he hung on to by a thread after leaving Detroit, five rounds ago. Now he has a rope. With one race left.

If Musquin indeed relinquished his third victory for Dungey's benefit he still grabbed second for his 10th podium this season and fifth in the last six rounds. He's finished runner-up five times this year. Jason Anderson (also teammates and training partners with Dungey and Musquin - though no word on the friendship component) rounded out the podium for this third-straight third-place result. Anderson grabbed the holeshot but a crash ended his chances for a season-best finish. Whatever happens in Vegas, Musquin claims the final spot on the Championship podium and Anderson gets fourth-place on the season.

Former MotoSport-sponsored rider Davi Millsaps took a season-best fourth-place and pulled to within four points of fifth-place Cole Seely, who reinjured an adductor muscle and pulled off. Seely missed Seattle and Salt Lake City because of the injury and if he remains sidelined on Saturday, Millsaps can post his best year since placing second to Ryan Villopoto in 2013.

Zach Osborne is one of four riders in the 250SX East class with a chance at the Championship

On the 250SX side, it's all 'bout that East, 'bout that East no West as Justin Hill wrapped up the 250SX West title two weeks ago with a third-place result while Shane McElrath took the win and Mitchell Oldenburg rounded out the podium in Salt Lake City. But, the East title fight could be one for the ages as one point separates the Top 3 riders and fourth-place Adam Cianciarulo still mathematically in it.

Jordon Smith leads Zach Osborne and Joey Savatgy by one point and a tie benefits Osborne since he's got four wins, the most of any of the East riders this year. Osborne won last week at MetLife Stadium and Joey Savatgy was on track for his fifth straight runner-up spot which would have increased his lead since Osborne entered Round 16 in third, six points behind Smith. However, Savatgy crashed, reentered the track at the wrong spot, finished third and got docked five spots thus giving Smith third-place while Dylan Ferrandis finished a career-best in second-place. Cianciarulo finished fourth.

Shane McElrath can't win the 250SX West Championship but can secure runner-up for the season on Saturday

The final 250 class race mixes both East and West with points given based on actual finish not on a sliding scale within the coast. So, even though Hill has little reason to ride, Shane McElrath needs a solid finish to hold onto second-place in the West as he holds an 11 point lead over Aaron Plessinger. Meanwhile, Martin Davalos is just a point behind Plessinger in fourth so second and third in the West needs deciding while four riders have title hopes and a stake for a spot on the Championship podium in the East.

Our Podium Picks for Las Vegas:

450 class:

  1. Eli Tomac
  2. Marvin Musquin
  3. Ryan Dungey

250SX

  1. Zach Osborne
  2. Shane McElrath
  3. Aaron Plessinger

Check out the track map for Round 17:

Practice and qualifying for Supercross Round 17 starts at 12 p.m. (PST) with Opening Ceremonies at 6:30 p.m. (PST) and the final gate drop of the year at 7 p.m. (PST) on Saturday at Sam Boyd Stadium in Las Vegas. Get your tickets online or at the box office. FOX Sports 1 provides live television coverage.

2017 Supercross Season Standings

450 class

  1. Ryan Dungey (341)
  2. Eli Tomac (332)
  3. Marvin Musquin (292)
  4. Jason Anderson (248)
  5. Cole Seely (212)
  6. Davi Millsaps (208)
  7. Blake Baggett (206)
  8. Dean Wilson (169)
  9. Chad Reed (167)
  10. Broc Tickle (167)

250SX East class

  1. Jordon Smith (160)
  2. Zach Osborne (159)
  3. Joey Savatgy (159)
  4. Adam Cianciarulo (146)
  5. Dylan Ferrandis (126)
  6. Christian Craig (97)
  7. Luke Renzland (84)
  8. Anthony Rodriguez (80)
  9. Kyle Cunningham (77)
  10. Mitchell Harrison (74)

250SX West class

  1. Justin Hill (190) - 2017 250SX West Champion
  2. Shane McElrath (154)
  3. Aaron Plessinger (143)
  4. Martin Davalos (142)
  5. James Decotis (122)
  6. Austin Forkner (105)
  7. Dan Reardon (96)
  8. Kyle Chisholm (85)
  9. Cole Martinez (73)
  10. Mitchell Oldenburg (60)