Stuart Broad is confident of being fit for England's first Test of the summer, against South Africa at Lord's next week, after suffering a heel problem while playing for Nottinghamshire last week. Broad said he was "sick with nerves" before coming through a full training session without discomfort the day before the Royal London Cup final, also at Lord's, and is set to return to action against Surrey.

England's Test squad will be announced on Saturday morning, with Broad all but certain to be included after passing himself fit for Notts. His availability - assuming he comes through the Royal London final unscathed - will come as a relief to England, after a number of injuries among the fast-bowling attack.

"I wouldn't declare myself fit for a Lord's final if I was not right," Broad said. "At the end of the day, you can walk on to any field, bowl your first ball and go down - that's cricket. But having bowled 100% in the nets, it feels good. I just have to keep managing it well, as you have to with your body when you get to 31. But yeah, I'm fit for tomorrow, which in my opinion, if I bowl okay, it means I'm fit for the Test."

Broad walked off after bowling one over in the second innings of Nottinghamshire's win over Leicestershire, having suffered a 1cm tear to the fat pad in his left heel. After being told by medical staff that such injuries usually heal at a rate of 1cm a week, he was left sweating on his involvement during "the biggest three weeks of the year", with the Royal London final and Lord's Test being followed by a Test at Broad's home ground, Trent Bridge.

Jake Ball, Broad's Nottinghamshire team-mate, has been ruled out for England after suffering a knee strain earlier in the week, while Chris Woakes was already absent with a side injury picked up during the Champions Trophy. James Anderson has only just returned from a groin tear, while Ben Stokes was hampered by a knee problem during the ODI series with South Africa last month and Mark Wood is on the comeback from a third ankle operation - although all three are expected to be in the Test squad.

"It was nice to get out today," he said. "I've felt sick with nerves for the last three-four days, because I've worked really hard for three months and played a lot of cricket, pretty much for the biggest three weeks of the year - Lord's final with your county that you've played every game for, Lord's Test and home Test. So obviously the first step is a tick, being fit for the Lord's final.

"The England guys have said it's up to me, I've played enough cricket to know whether I'm fit or not. You go into a Lord's final ready to bowl ten overs - you get through something like that comfortably then you're fit for a Test match."

Having played in all of Notts' Royal London Cup games, Broad still harbours ambitions of a one-day recall with England - "when Woakesy did his side, I was staring at my phone" - but the priority now will be getting him through a demanding schedule of seven Tests in nine-and-a-half weeks.

He will play with extra strapping on his foot and has had Ottis Gibson to stay at his house while working on technical issues to offset pressure on the heel but, ultimately, sometimes rest is the only cure. "A week without bowling, it seems to have, touch wood, done the trick," he said.

Alan Gardner is an associate editor at ESPNcricinfo. @alanroderick