Haas is the boost F1 needed, its midfield rivals admit

The American start-up team has scored 18 points from the sixth and fifth-place finishes at the Australian and Bahrain Grands Prix respectively courtesy of superb drives from Romain Grosjean.

Its performances may have raised eyebrows, but it has also drawn admiring comments, even from its nearest rivals.

Toro Rosso started the season with hopes of battling with the likes of Red Bull, but now finds Haas firmly among its rivals in a tight-knit midfield pack.

"After the first test we thought they would be where they are now, but then after the second we thought they would maybe not be much of a threat," said STR driver Carlos Sainz Jr.

"After Australia I wouldn't say they were particularly impressive, especially in the race I thought we were much stronger.

"But definitely at a track like Bahrain, especially with the power-unit advantage they have, they were impressive, and I congratulate them.

"They're a new team, and to do what they are doing, is top. It's incredible to see, exciting, impressive, but what F1 also needs.

"It's surprising everyone how good they are and how well they are doing.

"I've already congratulated them, and I will keep congratulating them because it's an amazing performance that they are doing.

"I just hope I can keep them behind at the next races."

Force India would also have expected to be comfortably ahead of Haas, especially having ended 2015 on such a firm footing.

But the team has so far struggled, especially in Bahrain with Nico Hulkenberg and Sergio Perez finishing the race a lap down in 15th and 16th after incidents.

Assessing Haas so far, Force India deputy team principal Bob Fernley said: "They've done a super job.

"You can't fault what they have done, and the car is obviously competitive, so I don't think there are any issues with that, but we obviously need to be battling with them."

Making reference to the fact the car is powered by Ferrari, and has numerous other parts from the Scuderia, Fernley quipped: "You've a September/October Ferrari with a paint job, so it should be good!

"But it's a serious programme and you should never underestimate that at all.

"It's well-funded, well-managed, with damn good drivers, and a good technical package to start the season with."