The former A-League player is set to sign a deal to become the Stags new first-choice custodian after Hyrulnizam was sidelined with injury
Pasfield was last with A-League side Central Coast Mariners having signed for them at the start of the 2011/12 season. The much-travelled custodian has been capped at Under-23 level for the Socceroos and has also had spells with North Queensland Fury, Newcastle Jets, Queensland Roar, Sydney FC, and Bray Wanderers in the League of Ireland.
The 28-year-old is now a free agent after being released from his contract with the Mariners at the end of the recent A-League season.
Goal understands that Pasfield is currently in discussion with the Stags to sign a potential short-term deal having flown into Singapore on Tuesday.
Hyrulnizam Juma'at meanwhile underwent surgery earlier this week for a back injury and is expected to be out for a few months. He last featured in Tampines' 2-1 win over Courts Young Lions last Friday.
Tampines had turned to a short-term signing to alleviate their goalkeeper crisis back in 2011 as well, when an injury to Hassan Sunny ruled the Singapore internaional out for the season. Former Etoile FC goalkeeper Yohann Lacroix was then signed as the Stags won the first of their three consecutive S.League titles.