A hat-trick to Joe Ravouvou has helped Bay of Plenty to a big win over Manawatu, and in the process secured them a home semifinal in the Mitre 10 Cup championship division.

The flying Fijian kept up his hot form, with the New Zealand Sevens rep making it five tries two games, as the Bay cantered to a 46-10 victory at the Tauranga Domain on Saturday afternoon.

The second-placed Steamers' seven-try bonus-point win puts them two points behind ladder leaders Hawke's Bay, with one regular season match to play, but they now can't be overtaken for home advantage in a fortnight.

At a venue where they had scored 50 and 51 in their two other outings this season, the hosts again piled on the points to dispatch a Turbos side who now have to win next weekend and hope other results go their way, in order to make the semis.

With a strong breeze behind them, Manawatu had opened the scoring through an early long-range Andre Taylor penalty goal, but it took the hosts just five minutes to hit back, with Ravouvou busting through some average defence on his 20-metre scamper, which came on the back of some superb offloading and short passing from his side's forwards.

And it was the Bay big men who proceeded to dominate, as the home side began to camp in the territory of their opponents, who, despite having that wind at their backs, had first five-eighth Otere Black constantly putting in just short dab kicks which didn't come off.

Turbos prop Fraser Armstrong was ousted early after failing an HIA and the visitors' scrum was under all sorts of pressure, coughing up three penalties on the trot and being handed a warning from referee Dan Waenga, with Bay No 10 Kaleb Trask slotting one of his two attempts from those penalties to give his side a five-point buffer.

But, for all their ascendancy, it wasn't until the final moments before halftime that Bay of Plenty were able to extend their advantage.

They went close in the 25th and 28th minutes, when firstly Ravouvou almost had a double before the TMO was able to spot a foot in touch, then fellow winger Emoni Narawa was dubiously pinged for a double movement when he was perhaps not held.

Manawatu didn't help their own cause, botching a golden chance on the counter attack when Ngani Laumape went over but for the TMO to rule on the obvious-looking forward pass from prop Sione Fa'alelei, then soon later a knock on close to the line from lock Sione Tuipulotu stunted a rare raid.

Then just before the break, in a half where they enjoyed 60 per cent possession, 73 per cent territory and an 'inside opposition's 22m' count of five minutes and 11 seconds to 41 seconds, the Bay were able to finally add to their tally, when hooker Kurt Eklund showed good power close to the line to spin out of a tackle.

The Steamers then turned with the wind at 15-3 and should have quickly had more points, but for a bemusing call from TMO Sam Fellows, who for some reason ruled out a 45th minute try to replacement first-five Jason Robertson for a supposed double movement.

After a lengthy delay due to Trask being forced off after coming off second-best in a collision with Laumape, the just-on-the-field Robertson had hit the line hard, but wasn't held when going again for the line.

The baffling decision didn't end up costing the Bay, though, as just a few minutes later they had their try, instead through Narawa, who coasted into the corner after a good shift right.

And the hosts then went back-to-back straight from the kickoff, with Narawa snaffling an intercept to set up an attacking wave, which eventually saw Ravouvou finish superbly for his double and the team's bonus point.

Then right on the hour-mark came the hat-trick, with an Aaron Carroll lineout steal handing the Bay attacking ball, then a beautiful cut-out pass from Robertson sent Ravouvou trotting down the touchline.

Manawatu got something to smile about when captain Jamie Booth charged down a Chase Tiatia kick and scored in the 63rd minute, but the Bay further stamped their mark with late tries to Richard Judd and Robertson giving the scoreboard a real reflection of their dominance.

Bay of Plenty 46 (Joe Ravouvou 3, Kurt Eklund, Emoni Narawa, Richard Judd, Jason Robertson tries; Kaleb Trask con, pen, Jason Robertson 3 con) Manawatu 10 (Jamie Booth try; Otere Black con, Andre Taylor pen) HT: 15-3.

Aaron Goile/STUFF