Explaining the rationale behind that choice, he said: "Joe's a great football guy and I've known Joe a long time".
"I have a clear view of exactly what's needed and that's what I aim to deliver - I do believe we will stay in the Premier League", added Agnew.
For the hosts, winger Gaston Ramirez has scored two goals in 20 Premier League outings as Middlesbrough bid to fend off relegation on their return to the Promised Land. "The players train really well every day, never a problem with attitude".
Assistant manager Agnew was handed the reins after Aitor Karanka was sacked by Middlesbrough on Thursday following a 10-game winless league run that saw the club slide down the table to 19th, three points from safety.
"Stewart's going to be a big part of the rest of the season for us", said Karanka's former assistant who will audition to retain the role for the remainder of the season at home to Manchester United on Sunday. In the second year, he took the team to Wembley to play the play-off final.
Proteas win toss, NZ to bat first
The left-arm pacer had left the field on Day Four of the Test match after bowling just 15 overs in South Africa's second innings. They've still got enough resources.
"So I think in the fourth year, he deserved to be sacked".
Agnew will oversee this weekend's clash with Manchester United and the Boro hierarchy will have two weeks before their next game due to the global break, giving them time to find a replacement.
Gibson has hinted that Agnew may be placed in charge until the end of the season, stating there is a "bit more steel" to Agnew than people realise and he "could be a surprise number one".
Steve Agnew is now in charge until Middlesbrough appoint a new boss. "He was "Get on with it, enjoy it and organise the team for the weekend", and that's as much as I wanted to hear", said Agnew.