SEAT 1200 Sport is a 2-door 4-seater coupé presented officially by SEAT in December 1975 and commercially launched from February 1976 to September 1979. Its huge importance for SEAT lied on the fact it was the first model of the Spanish brand entirely developed in its newly opened Martorell Technical Centre. When launched it was powered by the bigger 1,197 cc engine of 67 PS (49 kW) carried from the SEAT 124, which in this application was transversely mounted and canted forwards by 16°. This engine through a four-speed gearbox transmission gave the little 2+2 a top speed of 157 km/h (98 mph). Despite its sporting aspirations, power output was limited by a relatively low compression ratio, reflecting the fuel octanes available on its home market.

The sharp-edged body design had a drag coefficient (cd) of 0.37 and was purchased from NSU of Germany, after the German firm had abandoned its plans to launch its own small car, the based on the NSU Prinz rear-engined NSU Nergal model, presented as a prototype in the 1970 Turin Motor Show and designed by the Italian designer Aldo Sessano. It was Antoni Amat, the technical director of Inducar (Industrias de la Carrocería) i.e. an external provider for SEAT, the man who conceived the idea of proposing the whole project to SEAT with the mediation of Günter Óistrach, after the former's visit and contacts at the Turin Motor Show, with the Terrassa-based Inducar company undertaking from SEAT the production of the chassis for its SEAT 1200 Sport car. The purchased rights Nergal design had been sublimed to modifications in a mixture of elements with another Sessano's concept car i.e. the OTAS KL112, in order to fit in with the underpinnings meant to be used by SEAT, as it was based upon the ones of a Fiat 127. However the remainings of the original NSU Nergal design were still present in the SEAT production model: the air-vents in the third pillar just above the rear wheel arch were likely indicating the presence of the rear-mounted engine in NSU's donor design. In fact though SEAT's engineers first examined the possibility to keep the rear-engine layout in the SEAT 1200 Sport, they made the final choice in favor of a front-engined one. Its boot featured a remote opening through a handle on to driver's door and had a capacity of 339 litres.

In 1977 the SEAT 1430 Sport Coupé appeared, using the same body, but with a retuned version of the engine from the SEAT 1430. In this application the 1,438 cc engine provided a power output of 77 PS (57 kW) and a top speed of 164 km/h (102 mph).

The Sport versions were offered mainly in the Spanish market, but also some cars were officially offered in other European countries like Germany, Holland, Belgium or France. Both models, 1200 and 1430 were discontinued in 1979, along with the SEAT 128 the SEAT 133 and the CKD built Lancia Beta and Beta HPE, as part of the important re-structuring of the SEAT range for 1980. A total of 19,332 units were sold in the Spanish market, with 11,619 cars being equipped with the 1200 engine and some 7,713 units with the more powerful but late launched 1430 motor

The car was widely known as the "Bocanegra" because of the color and shape of its always black plastic front panel, which embraced the front grille and the headlights and incorporated, by 1970s standards, a prominent front bumper. "Boca negra" means "black mouth" in Spanish.

In 2008, SEAT presented the SEAT Bocanegra concept car at the Geneva Motor Show. It received this name as a homage to the classic 1200 Sport, as it also had a black front end. It is sold as a special edition Ibiza model from the second half of 2009, based on the SEAT Ibiza FR and Cupra versions.