Walker joined City for an eyebrow-raising £50 million from Tottenham last July, becoming the most expensive English footballer of all-time.
But the 27-year-old has proved a solid investment, establishing himself as a vital member of Guardiola's side, who head to Everton on Saturday two wins away from adding the Premier League crown to last month's EFL Cup triumph.
Along with lending width and penetration to City's attack from full-back, Walker's adherence to what Guardiola demands of his wide defenders – composure in possession and a willingness to come in-field and build play – has also impressed.
England manager Gareth Southgate cited Walker's development under Guardiola as a factor in him deploying the former Sheffield United youngster on the right of a back three during friendlies against Netherlands and Italy over the past week.
It was a test in an unfamiliar role that Walker passed with flying colours and he was named man of the match for his showing against the Azzurri.
"I think it was a good decision by Gareth Southgate," said Guardiola, who recently held talks with the Three Lions boss but insisted he did not plant that particular tactical seed.
"He can play in both positions. He has the physicality, he's intelligent, good at passing short and long, can go forwards and backwards fast. So he can play in a back three."
Opta data illustrates the transformation undertaken by Walker, who has curbed some of his more freewheeling attacking instincts to contribute to City's overall game.
Although he has supplied six assists this term to five for Tottenham in 2016-17, Walker created 15 more chances for Spurs, while his number of dribbles attempted and touches in the opposition box have halved – albeit in five fewer matches for City at this stage.
Walker's passing statistics tell a different story, with his accuracy up from 79.85 per cent to 87.83 per cent. He has completed 734 more short passes and a greater percentage of his passes now take place in the defensive half.
Guardiola famously deployed Lahm, widely viewed as one of the finest full-backs of his generation, in defensive midfield to fine effect and he sees similarities between Walker and the 2014 World Cup-winning captain in terms of their open-minded approach.
"Always when you buy a player, you guess and you imagine – 'okay, he can do that'," the former Barcelona and Bayern boss explained.
"But until you have them – training, training, playing, playing – you do not see whether they are able to or not.
"He [Walker] is open minded and when that happens anything can happen.
"In my past, I thought a guy cannot play in that position. After [training them] you think, 'wow – he can play in that position'.
"For example [Barcelona defender, Eric] Abidal and Philipp Lahm could play in different positions and adapt immediately, so quickly, because they were so good. Kyle is quite similar."
Such clear evidence of Guardiola's methods bearing fruit can be viewed as a reward for sticking to his guns following City's previous trip to Goodison Park - a crushing 4-0 loss last January.
"It was not a big problem at that time," he insisted, with City now on the verge of a Champions League quarter-final showdown against Liverpool and eyeing the prospect of sealing the Premier League title by beating Manchester United next weekend.
"I am not saying that because now we are in this position. I said last season, many times when I was asked, it works to play in the way I said. I never had a doubt about that."