Shawne Merriman tells TMZ Sports he's feeling pretty crappy today after learning Chargers owner Alex Spanos died ... saying, "Just really sorry for the loss, man."
Spanos -- who bought the Chargers back in 1984 -- passed away Tuesday morning at 95 years old ... just several weeks after his wife, Faye, died at 92.
"I sent text messages this morning to the family," Merriman, an ex-Chargers superstar, tells us.
"Very sorry to hear that. Alex Spanos has done so much for the organization."
Though Alex relinquished control of the Bolts to his son, Dean, in '94 ... Shawne says Alex and the rest of the Spanoses played huge roles in his development as a man after drafting him in 2005.
In fact, Shawne tells us the Spanoses are like family to him ... and he's hurting for them.
"Just want to send my love and condolences to the Spanos family."
George W. Bush also released a statement on Spanos' passing Tuesday, saying, "Alex was one-of-a-kind ... He was a wonderful citizen and friend, and the Bush family will miss him."
RIP.