To say Harry Redknapp likes a punt is akin to stating that day follows night; it’s a fact of life. However, the art of a good gambler is the ability to change his mind at the crucial moment and make the right decision on what might be a winner.

Redknapp would never have harboured doubts about Jermain Defoe, who again proved himself a poacher of the highest degree. The darting little striker, left on the England bench by Fabio Capello on Wednesday, grabbed both goals to break Middlesbrough’s recent stranglehold over Portsmouth in a stirring second-half comeback. He could easily have finished with four or five.

The element of calculated speculation came in Redknapp abandoning the 3-5-2 formation that had served his team so well in the emphatic win at Everton a fortnight earlier and reverting to a more traditional lineup, employing pace down the flanks and stretching the Middlesbrough defence to provide the openings for Defoe.

Newly acquired Algerian substitute Nadir Belhadj and Arsenal loanee Armand Traore were a nimble and creative duo down the left flank. John Utaka seemed even quicker down the right, although his final pass often left much to be desired. Nevertheless, Redknapp was more than satisfied. “You need a bit of pace these days, it frightens people,” he said. “I was excited at the prospect of trying this sort of system because the ability these lads have can cause all kinds of problems. And the little guy scores goals because he is strong and confident.”

The combination of Defoe and Peter Crouch, seemingly undeterred at being surplus to Capello’s requirements, is an exciting partnership perfectly equipped to capitalise on speedy raids that stretch the opposition defence. Once Redknapp changed things around, Middlesbrough’s full-backs were no longer able to augment their central defenders and Robert Huth in particular found himself increasingly exposed.

Portsmouth’s problem was not in creating chances but in stifling the threat of the opposition’s strike force. The prime requisite of a central defensive trio that liberates wing-backs to attack is that each man knows what the other is doing. This wasn’t the case as Chris Riggott clipped a speculative pass forward in 23rd minute. It fell short of the Pompey penalty area, but caused confusion between Younes Kaboul and Sol Campbell. Afonso Alves spotted the onset of panic and advanced a couple of steps forward to draw both defenders before slipping a neat ball into the path of Mido, who calmly slotted his low shot out of David James’s reach.

Redknapp’s patience with the 3-5-2 lasted until half-time and it was easy to see why he decided a change of formation was necessary. Kaboul in particular seemed so ill at ease that he managed to win a solitary defensive header throughout the first half. Within 13 minutes of the restart Portsmouth were level, although Middlesbrough were in effect down to nine men at the time. Didier Digard was prostrate requiring treatment after a heavy challenge and Mido was holding his face complaining of an eye injury. Stuart Attwell, at 25 the youngest referee in the Premier League, insisted play should go on and played a good advantage as Crouch was clearly fouled in slipping the ball through to Defoe to plunder a chance in a yard of space on the right-hand angle of the penalty area.

The defensive shortcomings of substitute Andrew Taylor cost Boro dearly four minutes from time when Glen Johnson perceptively chipped a pass into the opposition six-yard area. An attempted clearance was hashed and Defoe’s predatory instincts ensured he was perfectly placed to hook a shot past Ross Turnbull.