The 37-year-old premier batsman finished his playing career in the drawn second Test against South Africa on Friday, falling three runs short of becoming the country's highest scorer.
"It is not going to happen overnight," Lawson told reporters.
"It will take a year or two before we can find a replacement for Inzamam. He was a class player with experience which comes with time."
The former Australia bowler added it would be unfair to expect any of the current crop of players to start matching Inzamam's batting exploits immediately.
"There are a couple of good players in line but they will take time to mature and establish themselves as Inzamam did himself," Lawson said.
Inzamam retired after scoring 8,830 runs in Tests and 11,739 in one-day internationals but by only accumulating 17 in his final two innings, the batsman was unable to pass Javed Miandad's record aggregate of 8,832.
Miandad led the tributes for Inzamam on Saturday.
"I was expecting him to break my record. I would have been happy if he had done it, because I have had a teacher-student relationship with him," Miandad told Reuters.
"Given his service to Pakistan cricket and the quality player that he was, he deserved the record. I enjoyed watching him bat."
Miandad, who captained the side when Inzamam made his debut in 1992, said it was a sad reflection on the state of Pakistani cricket that it was not producing more players of his stature.
"We need to look at our system and ensure we groom more quality batsmen for a better future."
Former captain, Wasim Akram said that Inzamam had retired at the right time.
"He was one of the best batsmen produced by Pakistan along with Miandad," Akram said.
"The number of runs he scored is testimony of his greatness. It was sad to see him go but every player has to take a bow someday."