The Red Devils duo have endured a mixed season under new Dutch manager Louis van Gaal, which has been blighted by fitness and form problems.
England manager Roy Hodgson opted to start Jones alongside Gary Cahill for their 4-0 victory over Lithuania on Friday night, leaving Smalling on the bench.
Former Arsenal and England defender Keown reckons Red Devils duo Jones and Smalling still are lacking confidence under the United manager.
“Phil Jones and Chris Smalling are not really training on, they’re a disappointment at the moment,” Keown told talkSPORT.
“They’ve both looked nervous, particularly in the FA Cup game against Arsenal. Both looked like they needed an arm around them and I’m not sure they were getting that from their manager.”
“[Gary]Cahill and [Phil] Jagielka are the obvious partnership.”
Jones helped England keep a clean sheet at Wembley on Friday night as Hodgson’s side eased to a 4-0 victory over the Euro 2016 qualifying opponents.
Three Lions captain Wayne Rooney broke the deadlock in the clash before goals from Danny Welbeck and Raheem Sterling trebled the home side’s lead.
Tottenham striker Harry Kane scored on his England debut within 79 seconds of his introduction, guiding a header into the net following Sterling’s cross.
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