Shoaib Bashir has admitted he’s “not perfect” despite taking four wickets against New Zealand on the opening day of England’s first Test in Christchurch.

He took 4-69 to limit New Zealand to 319-8 at Hagley Oval. Rachin Ravindra, Tom Blundell, Nathan Smith and Matt Henry were all caught off his deliveries.

The 21-year-old made his Test debut against India in February and has impressed ever since. He has sent down the most deliveries (2,745) of any bowler in Tests this year – over 500 more than the next-busiest bowler in Sri Lanka's Prabath Jayasuriya.

Bashir, however, remains keen to improve despite his shining display in New Zealand.

"I wouldn't say I was disappointed but there was a bit of frustration when I was bowling out in Pakistan," Bashir told the Test Match Special podcast.

"I'm still 21, I've still got a lot of learning to do. I'm just enjoying every moment and I'm just so thankful."

Bashir had an economy of 3.45 on the first day, the third-best of the bowling attack, and bowled 20 overs, the most on the squad.

Only Indian bowlers Jasprit Bumrah (49) and Ravichandran Ashwin (46) have more wickets than the 45 that Bashir has claimed this year.

"I knew that if I did come on, I'd have a job to do and thankfully, I controlled the run-rate which was handy," said Bashir.

"I was bowling a touch slower but I was focusing on controlling my line with the wind.

"Because the wind was very strong, I was trying to focus on what I needed to do with my body to get the line I needed to bowl, which was outside off.”

His four-fer on the first day means Bashir is just one wicket away from becoming the only spin bowler to ever claim a five-wicket haul at the Hagley Oval.

But the on-loan Worcestershire bowler remains grounded about his abilities.

"I'm learning on the job and I'm not perfect. Two years ago I didn't have a county. I'm just very, very thankful for what has happened over the last year,” Bashir added.