"As a parent you drop your kids off at school many times," said Miami Dolphins coach Joe Philbin, whose 21-year-old son Michael fell into a Wisconsin river and drowned in January. "It's hard to put into words what that community and those families must feel like. We obviously kept them in our prayers."
A moment of silence was observed at all 14 NFL games on Sunday; in Houston and in Arlington, Texas, the scoreboard went black. Members of the Buffalo Bills and Seattle Seahawks stood quietly with their heads down on their sideline while fans stood silently at the Rogers Centre in Toronto.
The Bills did continue their pregame habit of playing U2's "Sunday Bloody Sunday," which they've played before every home game this season. The song is in reference to British troops shooting and killing unarmed protesters in Derry, Northern Ireland in January 1972.
In Chicago, Green Bay wide receiver Donald Driver retweeted the names of the victims. St. Louis defensive end Chris Long said after the 36-22 loss the Vikings that it was hard to feel sorry for himself.
"As we sit here and feel sorry for ourselves after losing a football game, it really helps put things in perspective," he said. "I was watching TV last night and saw a victim's parent and I was really moved by that, the strength that they were showing up there. If we can all show that strength, we'll be all right as a team and as people."
The Patriots, meanwhile, see Newtown as part of their New England base, and had a direct connection with Friday's tragedy.
The Kraft family, which owns the Patriots, also owns a box company, Rand-Whitney, that has a factory less than one mile from Sandy Hook Elementary School.
Rand-Whitney's parking lot was used Friday as a meeting area for media members after the tragic shooting at the school, a Patriots official said this weekend.
Information from ESPN's Rachel Nichols, Josina Anderson and Adam Schefter, ESPNBoston.com's Mike Rodak and The Associated Press was used in this report.