Gobern came in from the cold to start his first game since January 10 and was one of Town’s outstanding players as they all but secured their Championship status for another season with a 2-1 triumph over play-off chasing Ipswich.
Powell said: “When Oscar plays like that, he can change people’s views.
“I’ve looked at his time here and it’s been tough, but he’s always maintained his levels.
“David Edgar has done well for us away from home when we’ve needed to block things up or screen the defence, but I felt he (Oscar) would give us a bit more going forward and I felt we needed that at home.
“He did really well; he retained the ball, recycled it well and tackled and won headers.
“It was a good performance from him, ably abetted by Jacob (Butterfield) and Conor (Coady).
“I can’t fault anyone; I am really proud of how they dug deep. I have some good players, but it comes down to consistency.
“It is a tough league that tests you, but we’ve been very good against the better sides at home like Brentford, Watford and Norwich. Given that, roll on Derby.”
Reports linking outgoing Brentford sporting director Frank McParland with Town appear to be wide of the mark.
Town are considering their options in replacing Southampton-bound football operations chief Ross Wilson, who will leave this summer.
McParland was placed on gardening leave by Brentford in February, when it was announced manager Mark Warburton would be leaving at the end of the season.
While Town were left to bask in the glow of a rewarding Easter, which has yielded four points, Sheffield Wednesday have been reflecting on a disappointing sequence, which has accrued just a point.
The Owls went down 2-0 at Norwich on Monday and head coach Stuart Gray is demanding a big improvement against Charlton at Hillsborough this weekend.
He said: “Football is a simple game when you get it right in both boxes and we didn’t do that.
“I have said that to the players and I have told them I want to see a big improvement for Charlton on Saturday.”