BOSS Scott Parker admitted he will have to "rethink certain things" ahead of Saturday's Premier League opener, but reiterated his reluctance to play a back four.

Despite successfully guiding Cherries to promotion from the Championship at the first time of asking, mainly using a 4-3-3 formation last season, Parker has made a dramatic shift in tactics over the summer.

For each pre-season fixture so far, Cherries have lined up with three centre-backs, as they prepare for tougher tests in the top flight.

That has drawn some criticism, given Cherries' current lack of options in that position. Following the summer exits of Gary Cahill, Nat Phillips, Zeno Ibsen Rossi and Sam Sherring, only three senior centre-backs remain at the club in Lloyd Kelly, Chris Mepham and James Hill, the latter have played just two minutes of league football outside of the third tier.

Teenager Owen Bevan featured for the first time for the first team on Saturday, coming on during the friendly against Real Sociedad.

Parker is desperate for new recruits in central defence, but with the clock ticking ahead of the Premier League season commencing with a home clash against Aston Villa on Saturday, the boss is faced with a dilemma.

Asked if he could return to the 4-3-3 which worked so well last season, Parker said: "I wouldn’t want to. My experiences tell me that would be pretty tough.

"So I wouldn’t want to do that. But where we currently are, that may have to be an option. I’m not sure we will be able to defend well enough in a four and keep the door shut.

"At the moment in certain moments I think we look a bit vulnerable anyway.

"The next year in this league, the one thing we’re going to have to be is rock solid and we’re not going to be a team that can go and score three or four goals.

"So what we’re going to have to guarantee is that we can try and keep the door shut.

"It’s three losses on the bounce now for us, conceding some sloppy goals, poor goals really on our behalf. But we are now getting closer to the point, so we’ll have to work that out."

He added: "We’ve worked five weeks on a certain way, a certain shape, but I need to rethink certain things because I need to work out what we’ve got and the bodies we’ve got and how best to adapt for the start of the season really."

Rather than taking their place in the squad to face Real Sociedad on Saturday, first-team members Emi Marcondes, Jamal Lowe, Siriki Dembele and Ben Pearson instead got minutes for the development squad.

Just six players were named among the substitutes bench on Saturday, with five outfielders coming on in Bevan, Philip Billing, Jack Stacey, Kieffer Moore and goalscorer Junior Stanislas.

Asked if the starting XI he chose to face Sociedad was closer to the team we can expect to see line-up against Villa this weekend, Parker replied: "It’s the only XI really. I think that’s fair to say.

"A back five, you’re looking at a keeper that is really the only keeper. We’ve got Will (Dennis) behind him, obviously he wouldn’t be ready for Premier League football.

"A back five, which is the back five, there isn’t anyone else to play.

"Obviously there’s certain bits we can move around a little bit, but for large parts it’s where we are currently and the squad we have is what it is really."