Two red flags and a collision between Max Verstappen and Lance Stroll highlighted a heavily disrupted Practice 2 at the Portuguese Grand Prix.

The session began with all teams completing a test of Pirelli's developmental compounds for 2021 in the first 30 minutes.

All the tyres were unmarked, meaning it was unknown exactly where in the range this prototype was, but the Italian supplier would conduct long runs with some drivers and two shorter ones with others as they set the program.

Once that was completed, attention switched back to this weekend's rubber with Valtteri Bottas setting the pace with a 1m17.940s, as the soft compound was used for the first time.

As for Lewis Hamilton, yellow flags and traffic prevented him from setting a lap time on either of his first two attempts.

The session would then be red-flagged after Pierre Gasly's AlphaTauri caught fire in the final sector.

The Briton would improve up to sixth when the track went green again, but it was only a few minutes before the red flags were needed again.

This time it was for a collision between Lance Stroll and Max Verstappen at Turn 1.

The Dutchman had let the Racing Point through with two corners to go on and then slipstreamed alongside on the main straight.

Perhaps unsighted, Stroll would simply turn in with Max there and was pitched into the gravel trap as a result.

A lengthy stoppage left just eight minutes on the clock for a final few laps.

However, there would be no significant changes as Bottas' earlier best kept him P1, six-tenths clear of Verstappen in second.

McLaren would be the only team to improve significantly late on, with Lando Norris in third and Carlos Sainz in fifth.

Both Ferrari's also benefited from the disjointed session as Charles Leclerc took fourth and Sebastian Vettel sixth.

Highlighting how unrepresentative the positions were, Gasly still finished seventh despite his afternoon going up in flames.

Hamilton dropped to eighth as Esteban Ocon and Alex Albon completed the top 10.

When the session was active there was still plenty of incidents, such as Sergio Perez spinning at Turn 3 and Sebastian Vettel likewise at Turn 14.

Romain Grosjean also kicked up plenty of gravel after running wide at Turn 10.

Daniel Ricciardo and Nicholas Latifi were also lucky not to collide with the Renault having to avoid the Williams as it exited the pits at Turn 1.

An eventful 90 minutes which left Pirelli as the only real benefactors as they got the data they needed for their 2021 compounds.

That certainly sets up an unpredictable Saturday and Sunday to come.

Full results from FP2 can be seen below: