The organisers of the Miami Grand Prix have carried out some last-minute track changes ahead of qualifying day.
The Miami International Autodrome, built on the site of the Hard Rock Stadium, will play host to its inaugural Grand Prix on Sunday.
Cars took to the track for the first time on Friday as drivers looked to learn the 5.412-kilometre layout and perfect their set-ups, but the event's organisers were left with work to do overnight due to two problem points.
Two changes made ahead of qualifying day in Miami
The track at Turn 17, featuring a tight left-hander at the end of the circuit's longest straight, was resurfaced for the second time on Friday night.
That section of the venue was first resurfaced on Thursday after patches of damage began to appear.
In his event notes, Race Director Niels Wittich confirmed that "the apex at the exit of Turn 17 has been resurfaced", with the work having been completed in time for Free Practice 3.
It was also stated that changes have been made to the pit lane entry, which was designed and built to include a chicane to slow cars down before they reached the pit limiter line.
Upon inspection of the track, the FIA made the decision to move the pit limiter line to a position prior to the chicane, thus deeming the chicane redundant.
The chicane will remain in place, but its kerbs have been removed, replaced instead by bollards.
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Track changes come following driver complaints
The changes to the track come following a day of Friday practice that saw some drivers complain that the circuit lacked grip, with tyre marbles becoming a problem.
"I think when they clean the track, it helps," said McLaren's Lando Norris.
"This morning, there were a lot of marbles, and as soon as you went off-line, it was game over.
"It was the same in FP2. It started better, but then as soon as there's a little bit of marbles, you go offline and it's terrible, so I feel like it's not going to be great for racing.
"There's one line you've got to stick to, and that's it. It's a bit restricting, you can't do any differences compared to other people, so it limits you a little bit."
Norris still had some positive comments about the circuit, though.
"It's still a fun track," he added.
"It's challenging, it's difficult, it's obviously punishing, like I said, and still a fun-ish track to drive."
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