Fred and Scott McTominay were the victims of the sharp-tongued former Manchester United captain's latest outburst as he looked on unimpressed with their display.
Pascal Gross scored twice in the space of nine first half minutes for Graham Potter's side before an Alex Mac Allister own goal halved the deficit in the second period.
United huffed and puffed but could not find the equaliser.
Keane did not hold back in his criticism of his former side at full time and singled out their midfield pairing for vilification.
'The [lack of] decision-making and football intelligence from midfield, particularly Fred," Keane started while speaking as a pundit on Sky Sports.
'I've been going on about it for a long time – Fred and [Scott] McTominay are not good enough.
'They won't get Manchester United back competing at the top. We see it week in, week out. They're not up to it.'
Another United legend, Paul Scholes, echoed Keane's sentiments, telling Premier League productions: 'It was a shocking start for Man United and the first half was shambolic really'.
'The signs were there right from the first few minutes that this was going to be bad.
'McTominay was always trying to run with the ball, ridiculous. The quality in the middle of the pitch was really poor.
'I was happy he didn't get sent off [for a high challenge] but I think he was slightly lucky. Again, he's running with the ball, absolutely ridiculous.
'It could easily have been a red card. The quality in the middle of the pitch was nowhere near good enough but we've seen that for the last few years with these two players.
'With Fred and McTominay, he [Ten Hag] is going to have to go with just one of them but even one of them is probably too many.
'Fred gives the ball away all the time and McTominay's trying to run with the ball constantly and then gives it away. Pass it to your best players! It's not that difficult. It's criminal on a day like today.'
