Billy Brown believes new manager Pat Fenlon faces a "massive task" to turn Hibernian's fortunes around.
And Brown, who has been in caretaker charge of the first team, remains unsure about his future at the club.
Speaking after the 3-1 defeat to St Johnstone which Fenlon watched, Brown told BBC Scotland: "We just can't defend properly.
"I'll have to have a blether with Pat and see what he wants to do and we'll work it out from there."
Hibs led at McDiarmid Park through Richie Towell's strike but goals by Francisco Sandaza, Marcus Haber and Dave MacKay gave Saints the three points.
"I think it's typical of the performances of the players at Hibs this season," said Brown.
"We were in a winning position, doing all right, looked quite comfortable, defended all right.
"And then, in 38 minutes we lost a goal, 45 minutes we lost a goal and [again in] 47 minutes, a nine minute-spell.
"It's rank, poor defending, bad concentration and not enough resilience when you are ahead.
"That's why we're in the position we're in."
Fenlon was announced as the Leith club's new manager on Friday and Brown, who was appointed assistant manager to Colin Calderwood before the latter was sacked, is keen to remain working.
"I've got a lot of enthusiasm for the game left, I'm not finished yet," added the former Hearts number two. "So, we'll see.
"He [Fenlon] never spoke to the players after the game. It was me he wanted to have a wee word with about something.
"He's got a massive task. When you've lost the number of games that have been lost, the reasons stick out a mile.
"There's no point in kidding ourselves on, we're in a bad, bad position because the team, at the end of the day, is not good enough so it's got to be turned round.
"You can only turn that round with hard work, you can't go and sign 10 or 11 players to change it. So, it's going to be hard work to turn it round and it's going to be a big task."