The first involved a truck rollover at the intersection of Midland Highway and Powranna Road at around 7 a.m. yesterday.

While the driver and other motorists were unharmed, the crash partially blocked the road for the rest of the morning.

Police confirmed that one lane of Powranna Road was open shortly after midday, with the scene expected to be clear by 1pm.

The event preceded a serious single-vehicle crash in Underwood later in the afternoon.

Police and other emergency services were called to the accident on Prossers Road shortly after 3pm, where the driver had received "serious injuries".

The route was blocked from Osheas Road to Patersonia Road for several hours, with police remaining on the scene after 5pm.

Preliminary reports indicated that a blue Mitsubishi Eclipse Cross was travelling northbound when it veered off the road and collided head on with a tree.

A 48-year-old man from Newnham was the sole occupant of the vehicle and was transported by ambulance to the Launceston General Hospital where he remained in a serious condition as of 9.44pm yesterday.

The Northern Crash Investigation Services attended the accident in an ongoing analysis into the cause of the crash.

Any members of the public who observed the accident or have dash cam footage have been asked to contact the group.

Further information can be passed on to the police on 131 444 or Crime Stoppers on 1800 333 000 or at crimestopperstas.com.au. Information can be provided anonymously.