Manager Arsene Wenger knows Campbell well and has had him training with the club for weeks now, so he is perfectly placed to decide whether he think the 35-year-old can still cut it in the Premier League. Wenger will have tested him physically and analysed his fitness levels, both objectively and against those of the rest of his team. Any judgement will therefore have been made on a sound basis.
Campbell certainly knows the club well, having spent five years at Arsenal earlier in his career, so will immediately feel at home. And while he may have lacked motivation during his ill-fated spell at Notts County earlier this season, he will surely have no such problems when it comes to performing in the top flight.
I could not see a deal going beyond the end of the season, but if it gives Wenger reliable cover for William Gallas and Thomas Vermaelen at centre-back, then a short-term deal represents only a minor gamble.
The same can be said of Vieira’s move to resurgent City. Astute Eastlands boss Roberto Mancini can pull the plug in the summer if the Frenchman’s stay does not work out, but there is every reason to think it will. Vieira is more comfortable in possession than the man whose place in midfield he is most likely to take, Nigel de Jong, and is desperate to perform in order to win a place in the France squad for the World Cup.
The 33-year-old may be on his last breath, but he is motivated, will provide much-needed leadership and experience of winning top prizes, and has not cost a penny in transfer fees.
And he might just help Mancini keep City on track to challenge for the Premier League title.