Mick Mills lifts the Uefa Cup following Ipswich's victory over AZ Alkmaar in 1981
Ex-Ipswich captain Mick Mills believes a tilt at promotion to the Premier League is possible next season if they make the right additions this summer.
Town will play in the Championship in 2023-24 after finishing second in League One under Kieran McKenna.
They won 28 of their 46 games, amassing 98 points, but were pipped to the title by Plymouth Argyle.
"If we can improve it by about 20%, that'll be enough to make us serious contenders," he told BBC Radio Suffolk.
"I do believe we've got what it takes to be competing for the top six. It can be done. The investment is there, the running of the club day to day is perfect, Kieran McKenna is the right man for the job, he's got the playing side wrapped up nicely, but we've got to improve the team.
"We've got to go out and bring in good players, possibly five or six, of a certain standard, who might ultimately be our best players. We mustn't try to put people underneath what we've got, we've got to put people over and above what we've got."
Mills was in Bobby Robson's Ipswich side that finished second in the top flight in successive seasons in the early 1980s and also won the FA Cup in 1978 and Uefa Cup in 1981.
And some of the teams they regularly faced will be alongside them in the Championship next season, including Leeds, Leicester and Southampton, who have just been relegated from the Premier League.
"There are some very, very big names in there," said Mills.
"I listened to the radio the other day and they were talking about how competitive the Championship will be next year, they named a lot of big clubs and forgot to even mention Ipswich. But there's no way you can leave Ipswich out of that scenario.
"To be able to attract 29,000 supporters on a regular basis and have the history the club has got as well, they really are in there with everybody else."
Ipswich have released four players from their promotion-winning squad, including Richard Keogh and Kane Vincent-Young, and have offered new contracts to Massimo Luongo and Sone Aluko.
Mills believes two centre-backs should be a transfer priority, so McKenna has four to pick from for those positions, but says fans should not be overly worried about Town having to find a new level of performance.
"I think people are getting a little bit carried away with the standard, saying it's a lot better than Division [League] One. Maybe when you went down the division then the standard was a little bit lower but I do believe the top six or seven was really competitive," he added.
"I think the Championship is good but it's not so long ago that we were in there permanently [2002-19], we were the team that had been in there the longest and we coped as a club with it. It was only the last bit when things started to go wrong and we dropped down."
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