The NFL analyst explained on ESPN's "Get Up" on Monday he's so torn up by the tragic killing of the 46-year-old in Minneapolis, Minn. last month ... he's having a hard time putting his feelings into words.
"This spirit broke in this country. It broke," said Spears, who has three children. "It broke me."
Marcus -- who needed several seconds to wipe away tears, continued, "Everything that I've done in my life culminated to me having my children. And trying to give them a better situation."
Spears added, "This is a heart condition, man. What we're asking for help, and when we're asking for white people to understand, we need you to be against this."
"Not to tell us, not to ease and soothe by having conversations," the 37-year-old said. "We need you to be against this."