On one hand, he will have an alternative to the unpredictable and unreliable talents of Fernando Torres. The Spaniard has been unable to show any consistent form this season and it will be a welcome option for Benitez to have Ba at his disposal as an alternative up front.
Yet how will Ba really fit in? It is difficult to see how the player could play in the same team as Torres. Neither really work in any position other than that of the central striker, and you can be sure Benitez will not do as Ancelotti once did and try to accommodate two centre forwards by changing his system. Ba does not work so well out on the wing, because as he has put it, he does not like tracking back and doing the dull defensive work required of wide players in a 4-3-3. And Torres struggled when playing alongside Didier Drogba during the aforementioned experiment under Ancelotti.
Both players look to dominate the same areas, and Chelsea have enough problems as it is trying to get width into their play. Therefore Benitez will likely rotate. That will be interesting in itself, to see what effect it has. Torres has never thrived when being rotated, and it is a role he has only really had to play during his time at Chelsea. Both at Atletico Madrid and Liverpool he was the unquestioned number one up front, and thrived. At Chelsea, he has not done well in a team where he has not always been featuring on a weekly basis. Which means either Benitez has to risk trying this again or gamble on Ba, who may himself not enjoy the same level of form coming in from the sidelines too often.
If that does happen, even more pressure will be on Torres than there is already. Right now he is struggling to find consistent form without any pressure on him for his place. With a new forward breathing down his neck Torres will find the pressure intensifying and his ability to rise to that pressure will be severely tested.
For Ba, this is clearly a risk. The world knows of his degenerative knee injury and he needs to presumably play as much as possible to make the most of what is left of his career. It is reasonable to assume he won’t still be playing the game when most strikers are, around the age of 35. So Ba must make sure this one big move for him works out well. This may be the only chance he has to feature for a truly big team during his career. Thing is, this might be the last time Torres has that opportunity too.