New Sunderland boss fires promotion warning to Portsmouth, Hull, Charlton, Ipswich and Co.

Johnson succeeded Phil Parkinson as Black Cats manager last week.

The chief goal is to guide Sunderland back to the Championship – something Parkinson and Jack Ross failed to achieve while they were in charge.

After losing to Wigan Athletic in his first game in charge, Johnson oversaw the Wearsiders thrash second-placed Lincoln 4-0 at Sincil Bank on Saturday.

Sunderland currently sit seventh in the table and are four points behind Pompey with a game in hand.

Johnson was impressed with the Black Cats’ performance against the Imps.

And he’s adamant his side ‘will be successful’ continue to perform as the way they did at Lincoln.

Johnson told Chronicle Live: ‘That's the standard, on and off the ball, and in terms of the performance that was a very important win I feel.

‘It allows the players to believe, it allows the fans to believe, and what I'm really impressed with was just how well the lads have understood the protocol - I've fired in a lot of terminology and detail, but they have really taken it in.

‘I thought the compactness in the possession and out of possession, gave us the strength to break down what is a very good side.

‘That's the tempo and the template. There's mega-bucks of work to do, and one swallow doesn't make a summer, but that's now two results [including the win at Oldham] and two improved performances with just three or four coaching sessions.

‘My challenge now is to make sure I don't tactically fatigue the boys and don't bamboozle them.

‘We just need to keep the consistency. If we keep that consistency in this division for the rest of the season, we will be successful.

‘We've obviously given the others a bit of a head-start, but if we play like that consistently, we won't go far wrong. We've just got to rest and recover now, and go into the game on Tuesday with the same mentality.’