The Paraguay international replaced Sylvain Distin in the second half of the match at the Store First Stadium after sitting out the defeat to Austria Vienna at the weekend.
But he got his chance to impress against Accrington and Martinez felt it was important for the defender, signed from former club Everton earlier in July, to get some time on the pitch.
"It's important he got that first game and got to know his team-mates," Martinez told the club's website.
"It feels like he has been with us for a long, long time and he plays with that maturity.
"That is down to the group of players that we have who have welcomed the new signings really well.
"It's pleasing to see Antolin settle in really quickly. That's always a nice sign of a dressing room."