The Hoe Lane team travelled to Kent with high hopes, but these were dashed in an error-ridden game.
The hosts went ahead early on from a catch and drive with Josh Pankhurst scoring and Frank Reynolds converting.
Hertford hit back through skipper Josh Corcoran following some very good play through the middle of the pitch, latching onto the end of a pass and breaking through to go over. Ben Lloyd missed the conversion.
Tunbridge took full advantage of turnover ball, with Pankhurst stealing the ball and off loading to Tom Bailey to go over to make it 14-5.
James Kinsley was sent to the sin bin for not releasing in the tackle and the hosts took full advantage of the extra man with a kick and chase from Reynolds making it 21-5 at the break.
Hertford drew first blood in the second half to cut the deficit to 21-12, replacement prop Josh Hewitt powering through the middle after around 15 phases. Lloyd added the extras.
The visitors had a couple more chances to score but missed touch and dropped the ball at crucial times, handing the advantage back to Tunbridge who scored their bonus point try to make it 28-12.
Richard Streets made a break from the half way line, beating three defenders and the full back to score, and with Lloyd then kicking a penalty that put Hertford within six points at 28-22.
Another mistake by the Hoe Lane side saw Tunbridge pounce to go under the posts and extend their advantage to 35-22.
Hertford did at least pick up the bonus point try when James Keens crossed the whitewash.
“We coughed the ball up too much,” said Basra. “They scored two tries in the first half off our mistakes.
“You’re not going to win the game if you don’t keep the ball.
“The whole squad is disappointed. I didn’t give the lads a rollicking because the effort was there.
“It was a lack of skill and to be honest if it’s that then it’s up to the coaches to make sure we get that right.
“We wanted to start with a with but we haven’t. We have to move on from it as a group.
“We made so many line breaks but just didn’t finish it off.
“That was disappointing because we got over the gain line so many times but were then like rabbits in headlights.
“We didn’t have the composure to finish things off.
“We really need to get back on the horse this week and have a good game against Shelford.
“The effort and will to win was there but it was just of those bads at the office.
“You just have to almost park it and move on.
“We stuck to the game plan and what we know and tried to rugby but unfortunately it didn’t work for us.
“We had four players missing – Stuart Smart, Michael Sargent, Rory Seymour and new signing Harry Barker.
“We’ll maybe possible have three of those back in the mix for this Saturday.
“The lads who came in did well. Perhaps it was first day nerves, we weren’t able to finish off what we created which was a hell of a lot.
Hertford host Shelford, who lost 37-5 to Sidcup, this Saturday.
“I try not to look at the other results – anyone can beat anyone, but it’s tough to be on your mettle every game.
“We’ll have a big crowd there on Saturday we just need to perform.”
Updated 13:27 - 13 Sep 2018 by John Irvine