Matt Ulrich's wife, Alison, is speaking out after the former NFL player's death ... sharing an emotional post on Facebook where she remembered him as a great father, coach and friend.
"Our beloved, one-of-a-kind Matt has passed away and is in a better place," Alison wrote.
"Matt, we love you so so much. You are profoundly missed. We all want you back for just one more day."
Ulrich met Alison in the early 2000s when he was a star offensive lineman at Northwestern ... and the couple went on to get married and have four sons together.
In her post, Alison heartbreakingly said she wished she could have "One more hug. One more kiss. One more laugh. One more joke. One more wrestle with the boys" with him.
"It seems impossible to do this life without you," she said. "Please pray for peace and comfort for the boys. They have lost their greatest fan, coach and friend."
As we previously reported, Colts owner Jim Irsay announced the death of Ulrich -- who played two seasons for Indianapolis in 2005 and 2006 -- on Wednesday via the X app ... sharing his thoughts and prayers to the family.
"I am heartbroken to hear of the passing of Matt Ulrich," Irsay wrote. "Matt was with us only two seasons, but left his mark on many."
Ulrich joined the Colts as an undrafted offensive guard ... and he went on to win Super Bowl XLI with Peyton Manning, Marvin Harrison and Dwight Freeney.
A fundraiser was launched for his family following his passing ... and so far, it's raised almost $40,000.
A cause of death has not been announced at this time. He was only 41.
RIP