Surprise package Romania take on holders Germany in the European Under-21 Championships semi-final on Thursday in a heated atmosphere on and off the pitch in Italy.

A scorching 41 degrees Celsius (105.8 Fahrenheit) is forecast in the northern Italian city of Bologna when the match kicks off in the Stadio Renato Dall'Ara at 6:00 pm (1600GMT).

Romania technical director Mihai Stoichita fears it will be "too hot" for the players and has urged European football governing body UEFA to push back the time of the match, local media reported.

Four-time winners Spain and France line out in the second semi-final at 9:00 pm in Reggio Emilia -- 74km north-west of Bologna -- where forecasts for kick-off are around 32 degrees Celsius.

The Romanians have been the revelation of the biennial tournament finishing top of their group ahead of France, who advanced as the best second-placed team at the expense of hosts Italy.

Some 10,000 Romanian fans have been following the team as they booked their first semi-final berth after a goalless draw against France on Monday, ensuring a return to the Olympic Games next year for the first time since 1964.

The match in Cesena ended with clashes as Italy missed out as a result, with the girlfriend of Romania international Cristian Manea, hospitalised and receiving stitches to her lip amid the skirmishes.

Romania's stand-out player has been Ianis Hagi, scorer of two goals in the tournament and the 20-year-old son of national idol and former Real Madrid and Barcelona star Gheorghe Hagi.

Germany have on-form Freiburg forward Luca Waldschmidt, 23, scorer of five goals in three matches, and Augsburg's Marco Richter, 21, with three goals and two decisive passes.

France also have a big task in hand as they take on last year's runners-up Spain, who are looking to match Italy's record of five European titles.

The Spanish have reached three of the last four finals, lifting the trophy in 2011 and 2013, with France's only U21 trophy backing in 1988.

"(Past results) count for nothing. Anything can happen in match and we want to reach the final," said French centre-back Malang Sarr.

"Even Germany, Spain have had difficult moments (in this tournament."

Spain bounced back after their opening 3-1 defeat to Italy, edging Belgium 2-1 before whipping Poland 5-0.

France coach Sylvain Ripoll fears a "very technical and very mature" Spanish side powered by Real Madrid midfielder Dani Ceballos, voted the best player at the 2017 European U21 championships.

But the French are confident after emerging from a group which included England, who were for Ripoll "one of the favourites," and have already achieved their objective of a return to the Olympic Games for the first time since 1996.