but came up short against former King of the Cage Middleweight Champion Joey Villasenor losing by a split decision. In his next fight, he went on to face and defeat Marius Zaromskis, who battled Nick Diaz for the vacant Strikeforce Welterweight Title. Santos challenged Strikeforce Welterweight Champion Nick Diaz for the title on January 29, 2011 at the HP Pavilion in San Jose, California. He lost the fight via armbar submission in the second round. Santos was due to fight Paul Daley at Strikeforce: Fedor vs. Henderson but was forced to withdraw due to a shoulder injury. Santos fought Strikeforce newcomer Jordan Mein on September 10, 2011 at Strikeforce World Grand Prix: Barnett vs. Kharitonov. After a grueling back and forth fight "Cyborg" was defeated by Mein via TKO due to Elbows in the third round handing "Cyborg" back to back defeats, Santos has now suffered his fourth loss in his last six fights. After a long period of inactivity, Santos requested his release from Strikeforce to fight more consistently. His request was granted. Legacy Fighting Championship Santos was expected to face Pete Spratt at Legacy Fighting Championship 17 on February 1, 2013. However, Santos was forced to pull out of the bout due to injury and was replaced by Dan Hornbuckle. After nearly two years away from the sport, Santos returned to face Artenas Young in the main event during Legacy Fighting Championship 50 on January 22, 2016. He won the fight by unanimous decision. Gringo Super Fight Santos made his GSF debut on April 28, 2014, against Melvin Manhoef in a rematch from 2006. Santos, who was knocked out by Manhoef in their first outing, lost to Manhoef again via first-round knockout. Santos then announced his retirement shortly after the fight. Bellator MMA On March 1, 2016, it was announced that Santos signed a multi-fight contract with Bellator MMA. Santos made his organizational debut April 22 on the main card of Bellator 153 in a welterweight matchup beating Brennan Ward via first round submission. Making a quick turnaround, Santos agreed to fight Saad Awad at Bellator 154 on May 14, 2016 but lost. On July 16, 2016, Santos faced Michael "Venom" Page and was defeated via KO by a flying knee, resulting in a frontal sinus fracture. Santos retired in January 2017. He spent a year coaching in Curitiba, Brazil. In early 2018 he returned to the USA