Australia international Souttar has remained with the Foxes after back-to-back relegations despite intense interest in him from Championship clubs Sheffield United and Wrexham after he featured at the summer's World Cup.
He has stepped up as skipper in the new-look, youthful Foxes side under Martin, having been called upon just five times by Leicester in the past three seasons.
Souttar's only two appearances for Leicester last season came after they were already relegated, having spent the preceding 16 months recovering from a knee injury that he suffered while on loan at Sheffield United a season earlier.
And before that, he was barely called upon in the 2023-24 season by then Leicester manager Enzo Maresca who, like Martin now, placed a heavy emphasis on passing out of defence as part of the possession-obsessed approach that the club has committed to for a number of years.
Against Oxford, Souttar started in defence in front of veteran goalkeeper Alex McCarthy and alongside the experienced Luke Thomas, but the backline also included two novices in 20-year-old Jayden Joseph and Manchester City teenage loanee Christian McFarlane.
The pair were two of five starting players that were under the age of 22 and who have been turned to by the Foxes hierarchy to get them out of the third tier at the first time of asking after a long list of high profile and highly paid players – including ex-England midfielder Harry Winks, Denmark defender Jannik Vestergaard and Ghana forward Jordan Ayew - were moved on in the summer.
Souttar said the Foxes were "frustrated" by their shortcomings against Oxford, just days after Leicester earned their first league win of the season against Plymouth Argyle.
"In the Plymouth game midweek we looked really good and we felt we could kick on again. It didn't happen," Souttar said.
"We'll be men about it, I know that it was far from good enough. And we'll look back at the game, look at the moments that we've simply got to do better.
"All we can do as a playing group is put it right next weekend."
Leicester are in next in action on Saturday against Stockport County, who are third in the table and coming off a 4-0 win against Wigan Athletic.
