Andrew Crofts' 72nd-minute header ensured the Seagulls became the first team to beat Wigan at home this season in all competitions.
It was also a third straight win in the Championship as Garcia's men chase a place in the play-offs and it could have been more comfortable had Wigan keeper Lee Nicholls not saved smartly from Jake Forster-Caskey and Craig Conway.
"I am very pleased and proud of my players because of them gave 100 per cent and if you don't word hard it's impossible to win here," said Garcia.
"I'm pleased because no other team has won here and to be the first to do it means a lot to us.
"We had some good chances to score and they had one or two but we took our chance and it made the difference.
"All the players did very well and did their job and I'm proud of not only those that played but the substitutes - they were practising really hard this week.
"For us it's also important to have players coming back from injury as well.
"What we are trying to do is tell the players they have to show their abilities on the pitch and in training sessions.
"I don't want to speak about individuals because I want to talk about the group."
- Sports & Recreation
- Lee Nicholls