The pair featured for their new side in a narrow 1-0 defeat to Gomora United during their season opener at TUT Stadium on Friday.
Both players had been free agents since leaving Gallants at the end of the 2024/25 campaign.
Nange, an experienced holding midfielder, joined Gallants last season following a brief spell with SuperSport United in 2023/24.
The Limpopo-born player is best remembered for his time at Kaizer Chiefs between 2021 and 2023, where he enjoyed his most productive season in 2021/22, making 24 league appearances and scoring twice.
His stay at Gallants, however, proved less fruitful, as he managed just 13 appearances across all competitions with a single goal to his name before moving on.
Mahlatsi also spent one season at Gallants after joining on a free transfer in July 2024. The former Chiefs attacker made 20 appearances, contributing one goal and an assist during his short stint.
Their arrival at Leicesterfield City brings valuable top-flight experience to the newly rebranded club, which recently acquired the PSL status of JDR Stars.
Both players will be expected to provide leadership and depth as the Gauteng-based side looks to make its mark in the highly competitive Motsepe Foundation Championship.
Marumo Gallants coach Alex Lafitte expressed frustration with the Premier Soccer League's scheduling, even as his side earned a 1-1 draw against Kaizer Chiefs at FNB Stadium on Wednesday.
Sekhukhune United secured a late 1-0 victory over Golden Arrows in their Betway Premiership encounter at the Peter Mokaba Stadium on Saturday.
The Betway Premiership returns this week after the MTN8 semi-finals, and Tuesday's five fixtures promise excitement as clubs aim to build momentum or recover from slow starts.
As the Betway Premiership returns this weekend, all eyes will be on the newcomers to see how they adapt to the demands of top-flight football.
