Arsene Wenger criticised his Arsenal players after they slipped to defeat at Bournemouth on Super Sunday.
Hector Bellerin's scruffy finish to a fine move (52) looked like sealing a morale-boosting win for Arsenal, who were without the omitted Alexis Sanchez.
But the hosts turned the game around through Callum Wilson (70) and Jordon Ibe (74) to boost their survival hopes and further dent Arsenal's top-four ambitions.
Wenger lamented two costly mistakes that extended the Gunners' winless run to five games in all competitions.
"I feel overall physically it was a tough game for us," said Wenger.
"It wasn't forced errors, just a lack of decision making.
"We haven't created enough with the possession we had. We weren't sharp enough to create chances.
"Once you're 1-0 up you should create more chances. It's very frustrating and very disappointing, a very disappointing result for us, especially when you're 1-0 up.
"We made mistakes in areas where you wonder where they come from."
Wenger had admitted before the game that Sanchez's future would be resolved imminently, but while an end appears in sight to that saga, the on-field troubles continued.
Asked if Sanchez will be replaced if he leaves, Wenger said: "Yes. Look, if Sanchez goes we need to replace him.
"If players like Sanchez go we have of course to respond.
"Will he go or not, I don't know, but at the moment it's the transfer period.
"In this kind of period we try to use the players completely focused on being at the club.
"I don't master the rhythm of that but it could happen today, tomorrow, or not at all.
"That's why I didn't want to travel with him, and then suddenly he could go."