Orb finished fourth. The Kentucky Derby winner was a 3-5 favorite in Saturday's race, but he became another casualty of starting on the rail in the Preakness. Since 1950, only two horses have won the middle jewel of the Triple Crown from the No. 1 post position.
Orb's five-race winning streak ended on an overcast, windy day at Pimlico Race Course. The brown colt had not lost since Nov. 24.
Oxbow was coming off a sixth-place finish in the Kentucky Derby, where he made a move for the lead in the final turn but faded.
In the Preakness, Hall of Fame jockey Gary Stevens took control at the outset and never relinquished the advantage, winning this race for the third time in his career.
Oxbow covered the 1 3/16th miles in 1:57.54. He went off as a 15-1 underdog and paid $32.80, $12 and $8.80.
Itsmyluckyday finished second and paid $7.80 and $5. Mylute paid $5.20 to show.
Mylute, with Rosie Napravnik in the saddle, came in fifth in the Kentucky Derby. Racing at the track where she earned her first career victory, Napravnik was attempting to become the first female jockey to win the Preakness.
Lukas had three entrants in the nine-horse race. Titletown Five and Will Take Charge did not finish in the money, but the 77-year-old Hall of Fame trainer nevertheless made it to the winner's circle.
Oxbow bested Itsmyluckyday by 1 3/4 lenths.
For Lukas, the victory broke a tie with "Sunny Jim" Fitzsimmons for most Triple Crown wins.
It meant a lot to Stevens, too.
"It's so special," the jockey said. "Wayne, he supported me. Put me on my first Triple Crown winner. A lot of people were trying to get me off. He was the first guy to call me up and said 'I'm going to have a colt for you. His name is Oxbow.'"
Stevens added, "Wayne is like a brother, coach, a father figure to me."
Stevens almost couldn't believe how well it went.
"We came in here with a lot of confidence," he said. "When I hit the half-mile pole, I told myself 'Are you kidding me?' 'Is this happening?'"