Pozzi is in Poland having only just returned from a year away from the track through injury, but showed no signs of rust as he won his heat.
And Pozzi's time of 7.56 seconds was not only equal to his previous personal best – set back in 2012 – but also saw him progress as the joint fastest alongside Frenchman Garfield Darien.
"It was a great start but I feel sorry for my roommate Jamie Bowie having to get up at 6.30am with me," Pozzi said.
"It's always tough being in lane one with the faster guys on the other side of the track from me so I was a bit concerned about that.
"For me I was just focusing on my race and to get a good start. It was a good first round and I couldn't have asked for much more."
There was more good news for Great Britain & Northern Ireland in the 60m hurdles as William Sharman also won his heat, recording a personal best of 7.59 in the process.
Asha Philip made it three victories in three events, as the British champion went through her opening 60m heat in first place in 7.18.
GB & NI's youngest member of the team Sophie Papps equalled her personal best of 7.22 to advance to the semi-finals in second place behind world leader Murielle Ahoure.
"I've got the first run out of the way," Philip said. "Hopefully my legs will be fresh tomorrow and I should be good.
"I didn't want to take it too easy because you never know what can happen out there. Dafne Schippers wasn't that far apart from me and she’s a really good runner.
"I knew she was going to push me the whole way. I got through and that’s the main thing. Tomorrow should be a good day."
Both 4x400m relay teams topped their respective heats and qualified comfortably for the final. The men's quartet of Conrad Williams, Michael Bingham, Jamie Bowie and Luke Lennon-Ford maintained a lead throughout and eased over the line in a season’s best of 3:06.09 minutes.
The women's team followed the same example with GB & NI captain Eilidh Child giving the lead to Shana Cox before sisters Victoria and Christine Ohuruogu bought the baton home in another season’s best of 3:30.60.
Christine Ohuruogu said: "This year was about putting in an experienced team we are defending world champions so it was really important we put girls who know how to run indoors and are confident. All we can do is defend our title." Shara Proctor and Katarina Johnson-Thompson successfully navigated their way through to the long jump final after jumps of 6.69m and 6.60m left them in third and sixth place respectively.
However, after three failures at 2.28m in the men’s high jump, Robbie Grabarz and Tom Parsons bowed out of the competition at the Ergo Arena.
- Sports & Recreation