ASHBURN, Va. — Washington quarterback Robert Griffin III will miss Saturday’s exhibition game at Baltimore because of a concussion, reversing an earlier decision to let him play.

In a statement released Friday by the team, NFL independent neurologist Robert Kurtzke is quoted that Griffin “should be held from game play this weekend and be retested in one (to) two weeks before a firm conclusion to return to game play can be made.”

Griffin left last week’s exhibition game against Detroit with what Coach Jay Gruden said afterward was a concussion. The team announced Thursday that Griffin had been cleared to play this weekend.

Friday night, Griffin tweeted: “Trusting in God even when I don’t understand why certain things happen.”

Speaking to reporters for the first time since the game against Detroit, Griffin evaded questions Thursday about when – or even if – he sustained a concussion in that game.

“You’ve got to talk to the people who report that stuff,” Griffin said. “I don’t report that stuff. I was in the locker room, taking a shower, getting ready to watch the rest of the game, so I don’t know.”

So far, Griffin is 6 for 13 for 44 yards in two appearances, and Washington has not scored a touchdown with him on the field.

COWBOYS: Offensive lineman R.J. Dill, a third-year player who hasn’t appeared in an NFL game, has been suspended four games for violating the league’s policy against performance-enhancing drugs.

Dill said he failed a drug test in May, about six months after he said he underwent testosterone replacement therapy when he was not under contract with a team.

TITANS: A felony charge against wide receiver Justin Hunter has been reduced to a misdemeanor count of assault and battery.

Hunter had been facing a felony charge of malicious wounding that stemmed from a late-night flight at a Virginia Beach resort area during the July Fourth weekend.

The Commonwealth’s Attorney office said the case would go to trial Tuesday.

Friday’s games

CHIEFS 34, TITANS 10: Alex Smith threw for 171 yards and two touchdowns in less than a half, and Kansas City’s offense looked the sharpest it has all preseason in a weather-shortened victory at home.

The game was called with 3:50 remaining after thunder rumbled and lightning streaked across the sky.

Smith was 16 of 18 before giving way to third-string quarterback Aaron Murray just before halftime. Murray played the rest of the game, throwing for 146 yards with two touchdown passes and an interception.

Marcus Mariota got off to a slow start for Tennessee, misfiring on his first three throws. But the first-round pick out of Oregon was 7 of 8 for 99 yards the rest of the half.

LIONS 22, JAGUARS 17: Matthew Stafford completed 11 of 15 passes for 173 yards and two touchdowns, helping Detroit win at Jacksonville.

The Lions trailed most of the night, but rookie Zach Zenner’s 3-yard touchdown run with 1:41 remaining was the winner.

Detroit played without Calvin Johnson for the third consecutive game.