London:Pakistan captain Shahid Afridi said on Friday he would retire from Test cricket following the second Test against Australia at Headingley starting next Wednesday.
Afridi made his announcement after leading Pakistan to a 150-run defeat by Australia in the first Test at Lord's here on Friday.
The batsman, out slogging for two on Friday, said he no longer had the temperament for the five-day game after what was his first Test in four years.
"I've not been fully fit with a side strain and so I will not play Test cricket after the match in Leeds," Afridi said.
"I did the wrong thing," he told BBC's Test Match Special when asked about his decision to return to Test cricket after concentrating on one-dayers and Twenty20s in recent years.
"I think my temperament is not good enough for Test cricket and I am struggling with a side injury. I think maybe the next Test will be my last.
"The Pakistan Cricket Board asked me to play Test cricket, I wasn't thinking about it."
Afridi's announcement means Pakistan, who are set to promote vice-captain Salman Butt, were preparing for their sixth Test captain in three years.
Since Inzamam-ul-Haq retired in 2007, Shoaib Malik, Younus Khan, Mohammad Yousuf and Afridi have all led Pakistan, infamous for their instability, in the five-day format.
By contrast, Australia have had just four regular Test captains in 25 years - Allan Border, Mark Taylor, Steve Waugh and current skipper Ricky Ponting.
A perplexed Ponting told reporters: "I don't know exactly what has happened. Funny things happen around the Pakistan side."
Afridi was parachuted into the leadership after Yousuf and Younus were both omitted from the squad for this tour following bans imposed in the wake of Pakistan's 3-0 series loss in Australia earlier this year.
Afridi slogged what was just his fourth ball, from part-time off-spinner Marcus North -- who finished with a Test-best six wickets for 55 runs - and was caught on the boundary on Friday.
Afterwards Afridi, nicknamed 'Boom Boom' for his hard-hitting approach to batting, told a news conference it had been an irresponsible shot.
"The captain should be an example for the youngsters but that was not an example. I was in two minds whether to play my natural game or whether to take my time," added Afridi, who captained Pakistan to the World Twenty20 title at Lord's in 2009.
"You can say I was weak mentally...I'm not good enough for Test cricket."
Asked when he decided to quit Test cricket, Afridi replied bluntly: "When I got out."
After the Australia series, Pakistan stay in Britain for four Tests against England and Afridi said opener Butt, who top-scored in both Pakistan innings at Lord's with 63 and 92, should take over the captaincy.
"Salman is showing his maturity. He's good enough to take over this team as captain."
Yawar Saeed, the Pakistan tour manager, told AFP: "Yes, he (Afridi) has told us he is not feeling comfortable with the injury and has told us he doesn't want to play (Tests) but we will talk to him and then decide."
But Pakistan coach Waqar Younis appeared to have already accepted Afridi's decision to call time on his Test career.
"He believes himself he can't (go on) and it's hard to pressure him," former Pakistan fast bowler Waqar told Sky Sports.
"It was tough out there and he couldn't really manage it and that's one big reason for this."
However, Waqar said he hoped Afridi would continue in limited overs cricket.
"He will look only to play one-day and T20 cricket now," Waqar said.
"For sure he will come back for that and probably as captain. We really hope he will come back for that."
The 30-year-old Afridi has played 27 Tests since making his debut against Australia in Karachi in 1998, scoring 1,716 runs at an average of 36.51 with five hundreds and a best of 156 against India in Faisalabad in 2006. He has also taken 48 Test wickets with his leg-breaks.