Fortunately for Martinez, the scare seemed to clear Bautista's red mist and the closing stages saw attention turn back to the lead, with Simoncelli within one second of countryman Pasini with two laps to go.
The last lap began with the team Toth rider just 0.147sec ahead and Simoncelli dived instantly for the lead into turn one. Pasini cut back inside and the pair ran side-by-side through the following corners before Simoncelli held the position.
The pair passed and repassed each other several more times during a thrilling last lap, but Pasini was able to gain a few bikelengths heading into the final turn and won by 0.117sec at the chequered flag before milking the applause from the passionate trackside fans.
Reigning world champion Simoncelli got a frosty reception from the Aspar team in parc ferme, although the impending investigation helped Bautista keep a lid on his feelings. Simoncelli meanwhile did his best to display a happy 'business as usual' persona.
“A lot of things happened in this race!” smiled Simoncelli. “I got a great gap at the start then Mattia and Alvaro caught me quickly. I tried to pass Alvaro. I made a mistake because I thought I could [pass]. Instead Alvaro went fast and I had no space and we touched. I'm sorry. After I came back I tried to push 100% to take Mattia. It worked at the start of the last lap and I thought it was possible to win, but Mattia had a great last lap and today he is the best so congratulations to him. I am happy.”
“It has been a strange and difficult race,” stated Bautista. “Once I got my rhythm I caught Marco and passed him. He tried to pass me back at a corner without space to do so. He touched me and we went off track. After that I tried to regain the distance lost. When I arrived at Marco again I couldn't see anything because of the spray and I made a mistake. I am happy but I lost the race during the touch with Marco."
Depending on the outcome of the investigation, Bautista is now 7 points ahead of nearest rival Hiroshi Aoyama with Simoncelli, who failed to score at the first two rounds, 22 points from the top. Pasini is now up to fifth, 32 points from the lead.
“A win here in Mugello in front of these people is fantastic,” said Mattia. “When Marco touched Alvaro I stayed at the front and thought 'now we must stay here'. In the last lap I had a fantastic battle with Marco. It was an unbelievable win.”
The win was Pasini's second in the 250cc class, but first since his victorious debut at Qatar last season.
Scot Honda's Aoyama, who began the race just one point behind Bautista, couldn't match the wet pace of his closest title rivals and crossed the line in sixth position.
Race results- Mugello:
1. Pasini (Aprilia)
2. Simoncelli (Gilera) +0.117sec
3. Bautista (Aprilia) +1.293sec
4. Luthi (Aprilia) +24.557sec
5. Barbera (Aprilia) +27.014sec
6. Aoyama (Honda) +30.037sec
7. Debon (Aprilia) +31.325sec
8. Faubel (Honda) +35.178sec
9. de Rosa (Honda) +44.856sec
10. Locatelli (Gilera) +46.483sec