Lennie Lawrence says Bristol Rovers are in the market for a "tried and trusted" striker – preferably from the Championship – as they look to fill the void created by Rickie Lambert's move to Southampton.

Hitman Lambert agreed terms on a three-year deal with the Saints yesterday after the clubs finalised a transfer which could eventually earn the Pirates more than £1 million.

They are understood to be receiving around £800,000 up front for the 27-year-old marksman, who scored 29 goals last season and found the net 51 times in his 128 league outings for the club.

Although landing a replacement for Lambert is a top priority, Bristol Rovers are expected to strengthen the squad further before the end of the month.

With Steve Phillips expected to join Turkish club Ankaragucu in the next few days, they have already landed keeper Rhys Evans on a month-long deal, and he will make his debut in tonight's Carling Cup clash against Aldershot at the Memorial Stadium.

Director of football Lawrence said: "There are three weeks before the transfer window closes and options for loan signings are ongoing. I'll be looking to do something along both those lines as soon as possible.

"We have to bring someone in who can produce at this level – preferably from a Championship club. That's what I'd like to see.

"We want someone in their mid-20s who can still appreciate in value as well. You have to look at those things when you are at the stage of development we are. In terms of a striker, we want a tried and tested one.

"We will look to strengthen the squad in other areas and in a couple of other directions in terms of loans coming in as well as purchases. A little bit of a change in personnel won't hurt at this stage."

Southampton are believed to have made an initial approach for Lambert on Friday with the deal thrashed out over the weekend.

It is believed the Saints – subject of a recent takeover by Swiss businessman Markus Liebherr – have trebled the wages Lambert was receiving at the Memorial Stadium.

And Bristol Rovers say once that sort of money was on the table, the chances of the player staying put were virtually nil.

"We felt that this was the right move for a player who will be 28 this season – and the club," added Lawrence.

"The way things are done these days, where the player knows what his salary will be before the fee is agreed, made it a virtually untenable situation for us.

"I don't begrudge Rickie in the slightest, but people have to understand the situation that we faced.

"Rickie is, deservedly, the highest paid player in the history of Bristol Rovers by a long way and Southampton have doubled his wages.

"That makes the player unmanageable if you like, because that's a life-changing move, especially at his age.

"We had to bear that in mind, get what we consider to be the right price and I, in conjunction with the chairman, have negotiated to get the best possible deal.

"It has been a long, difficult, process and it's something we finally achieved yesterday.

"Obviously we are sorry to see him go, but we would like to reassure supporters that we will be working hard to improve the team and the squad and we will be looking to bring a replacement in at the earliest available opportunity.

"But we aren't going to pay over the odds and we have to use the money wisely to strengthen where we need to.

"I think that we can still go on and succeed in this league in spite of a disappointing start on Saturday.

"But we have to be careful how we allocate our resources and decide clearly where we need to strengthen and how we need to do it."

Bristol Rovers' chairman Nick Higgs, said: "We are all sorry to see Rickie go as it had not been our intention to sell him. But at this stage of his career, the contract offered to him by Southampton would have been irresistible to him, and we could not match that."