Pompey are six points above the relegation zone while Newcastle are four from safety but the Argentina international is convinced he made the right decision.
'I hoped I would have the chance to go to Portsmouth in January last year but I am glad that I came here,' said Gutierrez. 'The only worry is that we have five games and we have to win as many of them as possible.'
Mission: Jonas Gutierrez (right) has now regrets over joining Newcastle
The clubs play tonight at St James' Park in a game Newcastle must win if they are to have a realistic chance of survival.
'This is going to be my most important game for the club,' said the 26-year-old. 'We know exactly where we are so we must take the three points.
'The training has been very good and everybody is prepared for the game with Portsmouth. All the players are aware of just how serious this situation is.'
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