James Anderson admitted there was still room for improvement as he makes an attempt to regain full fitness ahead of the first Test against South Africa on December 26.
The 37-year-old paceman last turned out for England in the first Ashes Test back in August and had to withdraw from the field after bowling just four overs.
Still in the process of rediscovering his mojo, Anderson delivered 11 overs in two spells against an Invitation XI on Wednesday.
He said lack of match practice was disconcerting but aimed to bring his top game soon before the commencement of the four-Test series against the Proteas.
"I'm just looking to force my way into the Test side," he said ahead of a three-day match against South Africa A.
"I know I'm not up to match speed yet."
Anderson is England's all-time leading wicket-taker and his tally of 575 Test scalps is unmatched by any fast bowler in the format.
He conceded watching his team from the sidelines was personally frustrating and he felt the "hunger and desire to be back".
The Lancashire star reaffirmed confidence in his ability to acquire full match fitness once the Boxing Day Test gets underway.
"I think the second spell I bowled after lunch (when he took one for seven in five overs) was much better. I felt a much better rhythm. That's just the nature of bowling.
"I've bowled in the nets and in the middle in the last two weeks but you just can't recreate that match intensity. I think I was just a little bit off the pace in that first six overs.
"I'm sure if I bowl spell after spell in the next game, hopefully I will get better and better."
Anderson is expected to be an automatic inclusion in the England line-up alongside longtime new-ball companion Stuart Broad while Chris Woakes, Jofra Archer, Sam Curran and Mark Wood offer as other seam bowling options in the squad.