Monster Yamaha's David Philippaerts enters his home grand prix leading the premier MX1 class, after victory last weekend, while countryman Antonio Cairoli will aim to get the MX2 red plate back from current leader Tyla Rattray.
Philippaerts is the very first Italian to lead the MX1 world championship and, after winning his first race of the year - and first ever for Yamaha - will be on a high for his home event.
Teka Suzuki's reigning world champion Steve Ramon is Philippaerts' nearest rival in the points heading into the event, the Belgian sitting 17 points behind the Italian with Philippaerts' experienced team-mate Josh Coppins holding third, albeit another 17 points back.
After his 2007 heartbreak, Coppins was tipped to be the man to beat in 2008 - but an off season injury compromised his start to the GP campaign and the Kiwi will be keen to stop the top two pulling further away.
CAS Honda's Billy Mackenzie, who rides factory Honda machinery alongside team-mate Mike Brown and Martin Honda riders Marc de Reuver and Julien Bill, is the highest placed CRF rider in fourth, having shown the pace - if not the consistency - to win races.
Former series leader Ken de Dycker of Teka Suzuki has slipped back to fifth position, just ahead of two dangerous rivals, in the form of AXO KTM Silver Action's Jonathan Barragan and GPKR's Sebastien Pourcel.
The former was incredibly fast at Sevlievo, taking his first podium of the season and only missing out on a maiden GP victory when he fell from the lead in the closing stages of race two.
Pourcel meanwhile has already won three MX1GPs since his debut in the category in 2007, and arrives at Mantova having taken pole position at the last three rounds.
In the MX2 class, the Grand Prix of Bulgaria saw
Red Bull KTM star Rattray snatch the title advantage back from Cairoli after the Italian fell at the first turn of moto two and suffer two broken ribs.
