KANSAS CITY, Mo. -

Chiefs quarterback Alex Smith has agreed to a four-year, $68 million extension that includes $45 million in guaranteed money, a person familiar with the contract told The Associated Press.
    
The person spoke on condition of anonymity Sunday because the team had not announced the deal, which will keep Smith in Kansas City through the 2018 season.
    
The Kansas City Star first reported the agreement.
    
Smith and his representatives had been discussing an extension with the Chiefs for several months, and the veteran quarterback was hopeful a deal would be done before the regular season.
    
Turns out it was completed one day before the Chiefs were scheduled to have their first practice for their season opener Sunday against Tennessee.