"Enforced substitution, inspired substitution, depending on how you want to look at it!" reflected the City boss.

"Obviously you've a number of boys to pick from, and we decide to put Pato on.  And he's really got that bit between his teeth.

"We allowed him to go out on loan, effectively Derby sent him back, and we needed to have a serious conversation.

"When Jamie Paterson's mindset's on it, he's up there with one of the best touches and wrigglers and ball manipulators.

"I was very, very pleased with him today, and he's a top player when he's in that mood."

Johnson was also delighted to see Diedhiou, who saw an impressive first-half effort disallowed for offside, rewarded for an all-action display that on another day could have seen him grab a hat-trick.

The manager added: "To be honest, his form over the last six or seven weeks, he's deserved a goal.

"In the first half, that's a goal! It's an unbelievable strike and they've given offside against Marley Watkins, who is 30 yards away.

"He's done it in the second half as well and it's a great save from the goalkeeper to tip it on to the bar.

"But he's picked himself up and been there to score the second goal, and he definitely deserved that."

For Wigan boss Paul Cook, it was more frustration at seeing his side dominate possession without ever threatening to do much with it.

He said: "Bristol City came with a front two, they changed after half an hour to a (midfield) five because they couldn't control us in the game.

"We got in great areas, which we always do, and the lack of quality in the final third is there for all to see.

"If you don't score goals, you won't win games. And it has a very big habit of kicking us where it hurts at the moment.

"If we'd have drawn the game 0-0, we'd have all gone away bemoaning the lack of cutting edge. Unfortunately when you lose 2-0, the inquests are a lot deeper.

"It's getting all too repetitive now with us, unfortunately, it's such a disappointing day.

"We've had a problem scoring goals all year, everybody knows that.

"Within that, your job as a manager is trying to create a team that will score goals and will win games.

"We keep taking steps forward, but we have a terrible habit of being able to shoot ourselves in the foot."

Cook also confirmed Wigan have rejected a bid from fellow Championship side Cardiff for Wales international striker Kieffer Moore.