"We will not be complacent," he said on the eve of the match.
"In fact, we can't afford it," he said in reference to India's dominant display in the first international friendly on July 9 when Germanpreet Singh made the difference between the two sides.
The two international matches have been organised by All India Football Federation (AIFF) to help the U-23 team prepare for the forthcoming AFC U-23 Qualifiers in Doha where India have been clubbed with hosts Qatar, Syria and Turkmenistan in Group C, which kicks-off on July 19.
"I will be looking to improve on our performance as much I am sure Singapore would be looking to improve on theirs," Constantine stated.
The coach, however, wasn't willing to agree to the tag of 'dominant India'.
"Yeah, we wasted a great deal of possession and scored from the only shot on target," he said.
As the boys sweat out in the practice at the Choa Chu Kan Stadium with the USD 2 million villas watching from a distance on the far side, Constantine said: "We don't have any injury concerns."
"I am not someone to comment on my rival team but can say that Singapore have some skillful players in their squad who at times looked very good," said Constantine, under whose guidance India have now won nine international matches on the trot (including eight with the senior team).
The Indian contingent will head to Doha on July 15 once their commitments in Singapore end.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)