Northern Ireland's goal came thanks to a Matthijs de Ligt error, but Ronald Koeman defended the centre-back ahead of facing Belarus.
Netherlands moved top of Group C with a comeback win over Northern Ireland on Thursday but will be without Memphis Depay against Belarus.
Netherlands scored three late goals to overcome Northern Ireland, whose tactics left Ronald Koeman unimpressed.
Netherlands can go joint-top of Euro 2020 qualifying Group C by beating Northern Ireland, but Ronald Koeman foresees a tough contest.
Justin Kluivert is the one addition to Ronald Koeman's Netherlands squad for October's Euro 2020 qualifiers.
Netherlands rattled in four second-half goals against Germany, leaving Ronald Koeman impressed with their mental fortitude.
Matthijs de Ligt has remained calm despite his difficult debut for Juventus, according to Netherlands team-mate Virgil van Dijk.
Matthijs de Ligt is being used in the wrong position at Juventus, according to Netherlands head coach Ronald Koeman.
Ronald Koeman believes Netherlands made huge strides to reach the final of the Nations League but wants more cutting edge.
After the humiliation of missing Euro 2016 and the 2018 World Cup, the Netherlands have stormed back to football's top table.