Boult only arrived in the UK this week, but he trained on Wednesday at a ground where he has 12 Test wickets at 22.33 apiece
Trent Boult could still feature for New Zealand at Lord's in the first Test despite only arriving in the UK on Monday night.
The left-arm seamer has been a long-time star of Kane Williamson's attack, but Rajasthan Royals' run to the final of the Indian Premier League means he has left himself with little time to acclimatise ahead of the start of the series.
He trained on Wednesday, and Williamson described him as "keen as" to get going at a ground where he has 12 Test wickets at 22.33 apiece.
"Trent is obviously a world class player, and we've got a great variety in our bowling attack," said Williamson.
New Zealand are back on English soil a year after winning the World Test Championship at the Ageas Bowl, but Williamson insisted that his team would not "rest on matches that were played a year ago".
"So, although they're fond memories, and it wasn't all that long ago, there are always those challenges to try and address and move forward as a team."

Williamson is back fit for Test cricket after an elbow issue (Alex Davidson/Getty Images)
Williamson himself is only just back from a long-standing elbow tendon problem that has ruled him out of New Zealand's last five Tests.
"It's significantly improved, which is the pleasing thing," he said. "And obviously having that time out of the game was beneficial to get it back on track somewhat. Although it was a very frustrating period of grappling with it, it is nice to be back into full training and back into cricket really, which is really exciting and back with the team after watching them on the sidelines for a little bit.
"That we don't get that much Test cricket does make it a little bit more special especially to be playing at Lord's. Those are all special moments.
"For us, there is a lot of excitement to be playing Test cricket. The Test team are so passionate about the format. There does seem to be a real movement within cricket, but you certainly still see the purists get a real kick out of red-ball cricket, and the Test team are full of those sorts of people."