Peter Matthew Siddle (born 25 November 1984) is an Australian cricketer. He is a specialist right-arm fast-medium bowler who played mostly for Victoria in first-class and List A cricket, then also spent two seasons at Tasmania. In the Big Bash League, he was a foundation member of the Melbourne Stars, although he never played a game for them. He then had a short stint for cross town rivals the Melbourne Renegades, before a significant stint with the Adelaide Strikers. Siddle returned to play for the Renegades in the 2023-24 season. Since the 2024-25 BBL, Siddle has been playing with the Stars. He played Test cricket for Australia over an eight-year period from 2008 to 2016, before being recalled for the Test series against Pakistan in 2018. He retired from international cricket in December 2019. Siddle was part of the winning Australia team in the 2009 ICC Champions Trophy.

Early in Siddle's career he faced multiple injury setbacks, but was able overcome them in 2009 to be named the ICC Emerging Player of the Year. Though injuries continued to plague him throughout his career, he rose to prominence in the 2010–11 Ashes series when he became the ninth Australian to take a Test hat-trick, and the first Australian since Shane Warne in 1994–95 to do so in an Ashes test. He was also the first player in cricket history to take a hat-trick on his birthday. He remained a regular fixture in Australia's team until his bowling pace started to drop in 2014, with Australia's selectors beginning to focus on younger, faster bowlers.

Siddle became a vegan in 2012, subsequently receiving criticism that suggested his diet had a negative effect on his performance, which he disputed. He announced his international retirement on 29 December 2019, effective immediately.^{[citation needed]}

Siddle was born in Traralgon, Victoria and grew up in nearby Morwell in the Gippsland region. Originally a competitive woodchopper, he began playing cricket at the age of 14 for the Latrobe Cricket Club. As a teenager he experienced success, taking 11/47 in a state match at under-17 level. It was in that match that Siddle broke the Victorian state record set by John Scholes.

In 2003, Siddle attended the Australian Cricket Academy and made his first-class debut playing for Victoria against a touring West Indian team at the Melbourne Cricket Ground in November 2005. In 2006, he attended the academy again and was offered a full contract with the Victorian Bushrangers for the 2006–07 season. Shoulder injuries began to hamper Siddle, with a shoulder reconstruction sidelining him for most of the 2006–07 season and further problems interrupting the 2007–08 season. Despite his injury problems, he made himself an important part of Victoria's bowling attack, returning figures of 6/57 in an innings against South Australia, and taking nine wickets in Victoria's Pura Cup final loss to New South Wales. Siddle required a second shoulder reconstruction at the end of the season and, despite missing more than half of the season due to shoulder injuries, took 33 wickets at an average of 15.75 to attract attention from national selectors.

After touring India with Australia A, Siddle was named in the national 15-man squad for the four-Test tour of India on 12 September 2008, as back up to established bowlers Brett Lee, Stuart Clark and Mitchell Johnson. When Clark injured his elbow prior to the second Test, Siddle was selected in the match squad. He made his Test debut at the Punjab Cricket Association Stadium in Mohali on 16 October 2008. His first ball was a bouncer which hit Indian batsman Gautam Gambhir in the head, before taking his maiden Test wicket, that of Sachin Tendulkar. He picked up figures of 3/114 in the first innings, and finished the match with figures of 4/176.

Siddle lost his position in the team when Clark recovered, but regained his position in the team for the first Test against South Africa at the WACA due to Clark's elbow injury recurring. Siddle then solidified his place in the team during Australia's back-to-back series against South Africa. He broke through with three wickets in front of his home crowd at the Melbourne Cricket Ground during the Boxing Day Test Match against the Proteas on his way to figures of four for 81 in the first innings. Siddle backed this performance up in the next Test at the Sydney Cricket Ground, taking five for 59 in South Africa's first innings. His efforts were not enough, however, to prevent Australia from succumbing to a historic home series defeat.

Siddle also gave a fine account of himself on the South African leg of the rubber, in which the Australians triumphed 2–1. Going into the 2009 Ashes series, he had notched up 29 Test wickets at an average of 27.65. The fact that it had come in six Tests against the South Africans and one against India in India, with an economy rate of only 2.57 an over, helped make his record look even more impressive.