He was one of three debutants, alongside Jordan Cox and James Rew.
Baker had previously endured difficult white-ball introductions. On ODI debut against South Africa in September 2025 he returned 0 for 76 from seven overs, and in his T20 debut against Ireland later that month he took 0 for 52.
However, his Test start was more encouraging after England opted to bowl first. He struck in his seventh over, dismissing Rachin Ravindra, who edged to Jacob Bethell at gully, before removing Daryl Mitchell, caught by Emilio Gay at short mid-wicket.
By stumps he had 2 for 63 from 15 overs as New Zealand reached 291 for 7 from 77 overs, with Tom Blundell top-scoring on 51 and Glenn Phillips unbeaten on 49.
"I'm so thankful to have a proper debut that is reflective of where I'm at. My biggest learning from the Ireland debut was I felt like I wasn't being myself," Baker said, as reported by BBC Sport.
"Even last night I was struggling to eat, and fuelling as a fast bowler is super important. This morning I felt the anxiety build up in my stomach.
"I was pretty honest with people that I was pretty nervous going into the day. Once you start warming up, everything goes away and you get stuck in. It's actually been great.
"The lads have tried to put that behind us and deal with the situation as it is. The relaxed nature of the environment really helps from a nerves point of view."
New Zealand's middle order and England's inexperienced attack traded blows on an engrossing opening day of the second Test at The Oval, with the tourists closing on 291 for 7 after recovering impressively from a precarious position of 107 for 4.
New Zealand captain Tom Latham has confirmed that Henry Nicholls will step into the vacant number 3 role for the second Test against England starting at the Oval on Wednesday.
Jordan Cox and Sonny Baker are set to make their Test debuts for England against New Zealand after the hosts announced their XI ahead of the second game of the series, starting at the Oval on Wednesday.
England's preparations for the second Test against New Zealand have suffered another setback after Ollie Robinson was ruled out with a knee problem, leaving the hosts short on experience ahead of Wednesday's clash at The Oval.
