Max Verstappen completed a Friday practice double at the Spanish GP as he edged out Fernando Alonso and the impressive Nico Hulkenberg at the Circuit de Barcelona-Catalunya.
After being seven tenths of a second clear of the field in Practice One, Verstappen stretched his legs once again in Practice Two to be the only driver to dip below 1:14, posting a best time of 1:13.907.
Alonso ensured Verstappen's advantage was smaller in qualifying trim however, finishing 0.170s off the world championship leader as Aston Martin showed their pace in the afternoon after using the first session to gather data on their upgrades for this weekend.
"Fernando we thought would have his best chance of giving the Red Bulls a go in Monaco, but he's only a tenth slower here so that's positive and we potentially have a race on our hands," said Sky Sports F1's Naomi Schiff.
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Hulkenberg, driving at the Barcelona circuit for the first time since 2019, was a very impressive third for Haas, only two tenths off Verstappen's lead time and ahead of Sergio Perez in the sister Red Bull.
Esteban Ocon continued his fine form to pick up the fifth fastest time just ahead of the two upgraded Ferraris, with Charles Leclerc sixth and Carlos Sainz seventh.
Less than a tenth of a second covered Hulkenberg to Sainz to offer encouragement that Saturday's qualifying session could be closely fought even if Verstappen looks the man to beat for pole position.
But Mercedes will need to improve overnight to be involved in the battle for the front three rows on the grid after a disappointing day in the upgraded W14.
Having been more than a second off the pace in the opening session, George Russell could only manage the eighth best time of Practice Two and was 0.485s off Verstappen's benchmark.
Lewis Hamilton meanwhile was 11th, nearly a further two tenths of a second back, and the seven-time world champion is envisioning a tough ask to get into Q3 on Saturday.
"From the pace that I had today it's a struggle for me currently to get into the top 10 (in qualifying)," he said.
"Hopefully we'll do some changes overnight. I think it's very, very close between us and that middle after P5 back to P10 - it's really, really close between us all."
Schiff said of Mercedes: "It hasn't started very well for them this weekend and I think none of them will be happy to see that - these upgrades were so highly anticipated.
"They aren't the groundbreaking updates that are really going to bring them to the front of the pack but I think they were hoping for more than just that."
Russell was also forced to take evasive action into the gravel early in the session after coming up to the slow-moving McLaren of Oscar Piastri while on a fast lap.
Valtteri Bottas was ninth fastest to offer encouragement to Alfa Romeo for the rest of the weekend, with Pierre Gasly wrapping up the top 10.
And while Alonso was keeping close to the pace of Verstappen out front, it was another difficult session for his Aston Martin team-mate Lance Stroll who finished 18th in the timesheet with only the two Williams cars behind the Canadian.
Less than a second covered the top 17 cars to suggest Saturday will see plenty of battles in Qualifying to get into Q2 and Q3.
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