A Belgium side missing many of the stars that have helped them rise to the top of FIFA's world rankings were held 1-1 by Greece in a Euro 2020 warm-up on Thursday.
Martinez will be looking for a sharper performance in the Red Devil's second friendly against Croatia on Sunday. Belgium romped through to the finals as group winners with a 40-goal haul.
After their Group B opener in Saint Petersburg they go on to face Denmark and Finland.
In other warm-ups involving finalists for the delayed tournament Switzerland dished out a 7-0 drubbing to Lichtenstein, with Mario Gavranovic grabbing a hat-trick.
The Swiss are in Group A with Italy, Wales and Turkey who were also in action, seeing off Moldova 2-0.
Ukraine, drawn in Group C, edged Northern Ireland 1-0.
Elsewhere the Republic of Ireland came back from a surprise goal down in Andorra to win 4-1.