I hope Tashi's stunt did not ruin your idea for 'private duel between shinobi in moonlight' in Tanigakure. I thinked Tashi is kind of shinobi who places duty before glory. True if he had single handledly captured the man he would had gained fame. But he is already running low in chakra and the man seems tricky sort and dangerously so (what older shinobi is, that more experienced he is and so Tashi thinks he is toying with him with his tricks).<br/><br/>So Tashi thinks better way to serve Tanigakure is to sound alarm now that he has got confirm on his suspicion about the man being intruder, and if man does not have super speed boosts or stealth jutsu available, he cannot shake Tashi off him (altough Tashi is not skilled tracker nor spotter person, but he thinks alarming whole village up he trusts they can catch him if they get trackers on him).