Damián Emiliano Martínez Romero (এমিলিয়ানো মার্তিনেস), also known as Dibu, is an Argentine professional footballer who plays as a goalkeeper for Premier League club Aston Villa and the Argentina national team. Known as a specialist in saving penalty kicks, Martínez is widely regarded as one of the best goalkeepers in the world.

Martínez trained at Independiente's youth ranks before moving to Premier League club Arsenal in 2010. At Arsenal, he initially served as understudy, being loaned to various clubs, before breaking into the starting line-up in 2019, featuring in the Premier League and helping the club win a FA Cup and FA Community Shield. In September 2020, Martínez moved to fellow Premier League club Aston Villa in a transfer worth £20 million. In his first season at the club, he kept a club-record fifteen clean sheets in the Premier League.

Martínez was called up to the Argentina senior squad to replace Oscar Ustari to face Nigeria in June 2011. He received his second senior call up against Germany and Ecuador on 9 and 13 October 2019; he was an unused substitute for both friendly matches.

28-year-old Martínez made his international debut on 3 June 2021, in a 1–1 draw with Chile in a 2022 FIFA World Cup qualification match. He subsequently made his competitive debut in a major tournament on 14 June, once again in a 1–1 draw against the same opponent in his team's opening match of the 2021 Copa América at the Estádio Olímpico Nilton Santos in Brazil. In the 57th minute, he saved a penalty from Arturo Vidal, but he failed to prevent Eduardo Vargas from scoring on the rebound. On 6 July, Martínez saved three spot kicks in a 3–2 penalty shootout victory for Argentina over Colombia in the semi-final of the tournament. He went on to finish the tournament with a clean sheet in the 1–0 victory over Brazil in the final. Martínez was also awarded the 2021 Copa América's Golden Glove award as the best keeper of the tournament for his performances.

Considered to be one of the best goalkeepers in the world, Martínez is known for his distribution and shot-stopping ability. He has also been noted for his passionate style and bravado in goal, as well as his technique and mentality when stopping penalty kicks.

Martínez particularly garnered notoriety for his performances in penalty shoot-outs; in Martínez's four with Argentina as of July 2024, opponents have scored only 12 times from 24 attempts, a 50 per cent conversion rate, with Martínez saving nine spot kicks, with the other three misses being off-target. By the end of 2022, Martínez saved seven of the 35 penalties he has faced during matches throughout his career, as well as another three missed – resulting in a 71 per cent success rate for opponents. Combining the 59 penalties faced by Martínez in regulation and competitive shoot-outs during that time span, Martínez saved 13 and seen five missed outright – a 69.5 per cent conversion rate.

Martínez was given the names "Damián Emiliano" on his birth certificate, which caused confusion when he signed for Arsenal and everyone at the club was calling him Damián. "My name was actually going to be Emiliano Damian on my Argentinian ID," Martínez later explained. "But when my mum went to do it in the post office, I don't know where she done it, she was waiting hours and hours in the queue and when they done it they put Damian Emiliano first. To do it again she would have to wait two, three hours so she went 'it's ok, just do it like that, we're going to call him Emi anyway'. It was a bit confusing but now everyone calls me Emi. Damian used to be my grandad's middle name. My mum wanted just two names – Emiliano Martínez – but because my grandad passed away before I was born she wanted to put Damian in between the two names to have my grandad's name, nothing else."

He is nicknamed "Dibu" (abbreviation of Dibujo, Spanish for Drawing), after an animated character in the Argentine telenovela Mi familia es un dibujo. Martínez was given the nickname as a young player by former goalkeeper and goalkeeper coach Miguel Ángel Santoro at Independiente, at a time when the series was highly popular.