The Hard Corps (2006) on Netflix

Phillip Sauvage is an American soldier suffering from Post-Traumatic Stress Disorder stemming from his time in Iraq and Afghanistan. Sauvage joins Clarence Bowden, his former commanding officer, to work the bodyguard detail of ex-heavyweight boxing champ and now successful businessman Wayne Barclay. The release of notorious rap mogul Terrell Singletery from prison has caused Barclay's worried sister Tamara to take action by hiring Bowden and Sauvage, as Singletery has made threats in the past about doing away with the one man responsible for his incarceration -- Barclay himself. The first night does not go well for Sauvage and Bowden, as Bowden gets killed during an assassination attempt on Barclay by a Hummer full of Uzi-carrying gang-bangers sent by Singletery. It's up to Sauvage to continue the fight, which means bringing in a re-enforcement in his friend Casey Bledsoe, and training some new recruits chosen by Barclay. In an effort to "give back" to the streets that taught him toughness, Barclay insists that Sauvage use people from Barclay's gym as a team of bodyguards. But will they be enough to take down Singletery?