Former Dorsey Coach Paul Knox was smiling the entire game watching on TV.
"It was great to see him get a chance to play," Knox said.
Matthews, who went to Harbor College and Kentucky and was undrafted, hadn't made an NFL catch before Sunday.
"He's a great kid," Knox said.
Matthews played tight end at Dorsey, then started to develop his body at Harbor.
"He filled out a little, got a little faster, got a little bigger," Knox said.
Another Southern California player having a big game was former Valencia running back
Another player making contributions was former Sylmar defensive back Brandon Browner, who helped shut down Matthews in the second half for the Patriots.