The Saints star got his side a point at Manchester United after scoring to seal a late 2-2 draw.
The away side struck in the 95th minute to stop the Red Devils from marching into the top four.
And Hasenhuttl was very pleased for Obafemi to get the vital goal.
The youngster has often endured criticism from the manager and supporters this season.
Hasenhuttl told reporters: "I'm happy for him because it's not always easy for him.
"He came in and scored a fantastic goal.
"I'm very happy for him."