Beltran was born in Oceanside, California and raised in Carlsbad, California by a single mother. Beltran began boxing when he was 10 years old, and also was involved in street fighting from a young age. Beltran also began wrestling in middle school and was talented, but was initially not allowed to compete outside of practice because of poor grades. Beltran continued wrestling at Carlsbad High School during his sophomore year and picked up his grades, going on to compete on the varsity team as a Heavyweight for all three years and also became involved in Greco-Roman Wrestling. Beltran originally attended the University of Hawaii at Manoa before dropping out and then being introduced to mixed martial arts. Beltran moved back to California, attending Palomar College and continuing with mixed martial arts. When he began training, Beltran weighed 300 lbs.
Beltran made his professional debut on February 10, 2007 at Strikeforce: Young Guns and lost via unanimous decision. He went on to compile a record of 6-2 before being signed by Bellator.
Beltran made his Bellator debut at Bellator 5 on May 1, 2009 against former UFC veteran Sherman Pendergarst. Beltran won the fight in the first round via TKO.
In his next appearance, under the King of the Cage banner, Beltran defeated Wes Combs via TKO only 25 seconds into the fight.
Beltran picked up another TKO win over another UFC veteran, Houston Alexander, before being signed by the UFC.
Beltran made his UFC debut at UFC 109 against Brazilian jiu-jitsu black belt, Rolles Gracie. Beltran was stepping in as a last minute replacement for Gracie's original opponent, Mostapha Al-turk. Beltran upset the fatigued Gracie and was victorious via a second round TKO.
Beltran returned to action on May 8, 2010 at UFC 113. He was originally set to fight Chad Corvin, but after Corvin's paperwork was not approved by the Quebec Athletic Commission he was pulled from the card and replaced by Tim Hague. Beltran defeated Hague after three rounds, taking the unanimous decision (30-27, 30-26, 29-28).
Beltran next faced Matt Mitrione on September 25, 2010 at UFC 119. Beltran fought and lost to Mitrione via unanimous decision (29-28 on all cards). Even though he lost, he still earned Fight of the Night honors.
Beltran then fought highly regarded kickboxer Pat Barry at UFC Fight for the Troops 2 on January 22, 2011, in Fort Hood, Texas. He lost the fight via unanimous decision. During the fight, Beltran received a high volume of leg kicks from Barry, a former K-1 kickboxing competitor, yet only collapsed at the end of the final round. Barry has since expressed his bewilderment at the level of punishment that Beltran was able to absorb.
Beltran was expected to face promotional newcomer Dave Herman on June 11, 2011 at UFC 131. However, after Herman was shuffled to the main card, Beltran instead faced another UFC newcomer in Aaron Rosa. After a back-and-forth first two rounds, Beltran defeated Rosa via TKO in the third round.
Beltran fought Stipe Miocic on October 8, 2011 at UFC 136, losing via unanimous decision.
Beltran faced former Strikeforce. Heavyweight Lavar Johnson on January 28, 2012 at UFC on Fox: Evans vs. Davis, where he was knocked out for the first time in his career in the first round. Following the loss, Beltran was released from the promotion.
After being released, Beltran announced that he would be dropping down to compete in the Light Heavyweight division. He officially made his Light Heavyweight debut on April 28, 2012 at C3 Fights in Oklahoma, where he defeated Anton Talamantes via unanimous decision.
Beltran made his return to the UFC replacing Brandon Vera against Australian James Te Huna on July 11, 2012 at UFC on Fuel TV 4. Although Beltran lost via unanimous decision, the back and forth bout earned Fight of the Night honors.
Beltran was expected to face Anthony Perosh on December 15, 2012 at UFC on FX 6. However, Perosh was forced from the bout with a toe injury and replaced by Igor Pokrajac. He won the fight via unanimous decision. On January 10, 2013, it was announced that Beltran had failed his post fight drug test, testing positive for nandrolone. Beltran was subsequently suspended for 9 months, retroactive to December 14, 2012. His win over Pokrajac was changed to a No Contest.
Returning from his suspension, Beltran faced Fábio Maldonado on October 9, 2013 at UFC Fight Night 29 in Maldonado's home-country of Brazil. He lost the back-and-forth fight via split decision. He was subsequently released from the promotion.
On October 30, 2013, it was announced that Beltran had signed with Bellator MMA. He faced former UFC Light Heavyweight Champion Quinton "Rampage" Jackson on November 15, 2013 in the main event at Bellator 108. He lost the fight via TKO in the first round. Beltran faced Vladimir Matyushenko at Bellator 116 on April 11, 2014, winning by third round submission, his first submission win since 2007.
Beltran challenged Emanuel Newton for the Bellator Light Heavyweight Championship at Bellator 124 on September 12, 2014. He lost the fight via knockout in the third round.
Beltran made his Middleweight debut against Brian Rogers on April 10, 2015 at Bellator 136. He won the fight by majority decision.
Beltran next faced Kendall Grove at Bellator 143 on September 25, 2015. He lost the fight via TKO in the third round.
On September 21, 2016, it was announced that Beltran would be facing Alessio Sakara in the co-main event of Bellator 168 on December 10, 2016. He lost via knockout in the first round.5150 Combat League / Xtreme Fighting League
5150 Combat League Heavyweight Championship (One time)
Ultimate Fighting Championship
Fight of the Night (Two times) vs. James Te Huna and Matt Mitrione