Maynard was killed while in his car with police now searching for two suspects who are reported to have escaped the scene on a black scooter.
The 32-year-old was helped by officers at the local fire station, but he later died of his injuries.
Maynard last played at non-league Dutch club Alphense Boys, but also enjoyed a spell at Royal Antwerp before featuring for the Brewers from 2014-16.
Maynard was limited in his appearances due to injury, but was involved in the squad that won promotion to League One in 2015.
A statement from the League One club read: ”Everyone at Burton Albion is saddened to learn of the tragic death of our former player Kelvin Maynard.
“Our sympathies go out to all his family and friends at this difficult time.”
The Dutch-Surinamese player began his career with FC Volendam in 2006 and also featured for Emmen and Spakenburg before playing in the amateur leagues of the Netherlands, including time with Quick Boys.