Babar Azam was on top of the world two years ago -- Pakistan captain and top-rated batsman in all three formats -- but he will celebrate his 30th birthday at home on Tuesday when the second Test against England begins in Multan.

Pakistan on Sunday left out Azam from the second Test squad after a poor run of form where he has failed to pass fifty in his last 18 Test innings.

It is the first time Azam has been dropped from the Pakistan team since his white-ball debut against Zimbabwe in Lahore in 2015 and Test baptism against the West Indies a year later.

Azam shot to prominence with three successive hundreds in an ODI series against the West Indies in 2016.

He replaced India great Virat Kohli as world number one ODI batsman five years later, a place he still occupies having been briefly deposed in between.

He is still ranked fourth among Twenty20 batsmen but it is the long format where his form has suffered the most and his slump has seen him fall outside the world's top 10.

A 13-year-old Azam was a ball boy in Pakistan's Test against South Africa in Lahore in 2007, where he could watch his childhood idol AB de Villiers.

From the streets of Lahore he rose to play in the 2010 Under-19 World Cup in New Zealand, topping the batting charts for Pakistan with 298 runs in six games.

Two years in at the U19 World Cup in Australia he was captain and again leading run-scorer, with 287.

In 2015 he was picked for the senior side and after thrilling in the white-ball game developed into a modern-day great in all three formats, often drawing comparison with Kohli.

- Pressure takes toll -

His opening partnership with Mohammad Rizwan in Twenty20s has realised 3,268 runs in 70 innings -- the most by a pair in the format.

He anchored Pakistan's only T20 World Cup win over arch-rivals India in 2021 in Dubai.

He hit an epic 196 against the famed Australian pace attack of Mitchell Starc, Pat Cummins and Nathan Lyon to draw a Test in Karachi in 2022 -- hailed as one of the greatest innings in Pakistan.

But the pressure of captaining a struggling Pakistan took its toll and began to affect Azam's form with the bat.

Following Pakistan's first round exit from the 50-over World Cup in India last November, where his side lost to Afghanistan for the first time, Azam stepped down from the captaincy in all three formats.

When the Pakistan Cricket Board hierarchy changed in April this year he was reinstated as white-ball skipper.

But it proved to be a short-lived tenure as Pakistan lost a T20 to Ireland before crashing out of the T20 World Cup in June after being stunned by the USA and losing to India.

He resigned as white ball captain for a second time earlier this month.

But it was in Tests where his form deserted him the most and a poor run in the series defeat against Bangladesh last month saw him score just 64 in four innings.

His 30 and five on a faultless Multan batting wicket in the first Test defeat against England, coupled with the formation of a new selection panel straight after, saw him left out for the second Test despite a vote of confidence from captain Shan Masood and his coach Jason Gillespie

He was seen in an emotional discussion with Gillespie on Sunday at Multan stadium before leaving the squad for the journey home to Lahore.

The break from cricket will give a tired Azam time to rest, reflect and recuperate, after two years of mental, emotional and physical toil on the front line of a struggling side.

"We are confident that this break from international cricket will help these players, especially Azam, regain their confidence," said selector Aaqib Javed.