He may be jumping ship but Ben Castle is adamant he's not leaving the Steamers rudderless.

In fact, the Toulon-bound tighthead prop can see positive signs in his departure from Bay of Plenty rugby that may bode well for the province he graced for six seasons.

With the Steamers rocked by the twin exits of Castle and fellow Chiefs prop Simms Davison, the Steamers have drafted young Wellington prop Arden David into their 2008 squad, something Castle finds ironic.

"Rugby's going through a cycle of people heading offshore but it's opening up a lot of opportunities for new players," the Wellington-born 28-year-old said.

"It's probably a bit more motivating for guys like Matt Wallis and James McGougan to know that Simms and I aren't there _ I certainly don't doubt their ability and I hope they take this opportunity to nail this opportunity for a starting spot in the Steamers."

Castle admits it was a big call to leave the Steamers after making his debut against Italy in 2003, though the offer out of the blue from Toulon simply brought his plans forward by six months.

"It's something that may not ever pop up again so you've got to take it.

"I'm off contract with New Zealand and Bay of Plenty at the end of this year and it's a natural thing to do to consider all your options _ my goal was to play some rugby offshore at some stage and it probably would have been a good time at the end of this year.

"I'd already had a couple of options fade away [due to] timing and then this one came along _ Toulon did give me a bit of time to try and get things sorted though and I was able to seek a release."

The release wasn't entirely straightforward. Bay of Plenty, still reeling from a $915,000 loss in the last financial year, sought compensation from Castle for salary already paid this year _ but the prop certainly wasn't bearing any grudges.

"It's quite an emotional thing because it's a union that I've become so hugely attached to for so many reasons. The big one was the opportunity they've given to me and how good they've been to me in the last five or six years _ I'm just really grateful for the time I've had with the Steamers.

"I'd have no hesitation coming back here _ Bay rugby would be one of the first phone numbers on the list of people I'd contact when I've finished overseas."

Now he's about to link up with former All Black skipper Tana Umaga, who has overseen Toulon's promotion into the French top-14 competition.

He only met the dreadlocked former centre recently, despite playing him a number of times on the field, but was impressed by Umaga's no-nonsense approach.

"He's got some pretty good ideas and he's very well respected where he's coaching now. It always helps having a Kiwi-speaking coach and a guy who understands how rugby is played here."

Toulon already have former All Blacks Saimone Taumoepeau and Nathan Mauger on their books, have recently signed flanker Jerry Collins and will field either All Black point-scoring record-holder Andrew Mehrtens or incumbent first-five Dan Carter during the next season.

Toulon president Mourad Boudjellal announced at the end of last season that building the front line would be his priority _ the club is also close to signing Stade Francais prop Franck Montanella and South African hooker Tiaan Liebenberg.

Castle and Davison's departure is further grim news for the Chiefs, who have already lost hooker Tom Willis (to Wales), and locks Jono Gibbes and Kristian Ormsby are tipped to join the exodus.

Chiefs coach Ian Foster is adjusting to losing his entire front row from this year.

"It's one of those facts of life at the moment at Super Rugby level in New Zealand," Foster said.

"Simms and Tom have been well established in that starting lineup in the last two or three seasons [and] Ben has been there for a while but has probably saved his best rugby until this year."