The 54-year-old is thought to have been hit by a car which did not stop, and was then hit by a second car moments later which did stop.
The victim died at the scene of the collision, which happened at the junction of Bagot Street and the A38 heading out of Birmingham, shortly before 10pm last night.
A short time later, a man was arrested at an address in Willenhall in Walsall on suspicion of causing death by careless driving while under the influence of drink.
The 32-year-old remains in custody this morning.
A number of vehicles have been recovered as part of the investigation, and a number of drivers have been spoken to already.
Specialist officers have been working at the scene overnight to investigate how the tragedy happened, but the road has now opened again.
PC Chris Ridge, from West Midlands Police serious collision investigation unit, said: “The man’s family have been given the very sad news, and our thoughts are with them today.
“We’re still trying to establish exactly what happened, and have already spoken to a number of witnesses.
“Sadly, we believe the man may have been hit by a number of vehicles while in the road, and it’s possible those motorists are unaware that they have been involved.
“If you were driving in the area at the time, or have dash cam or mobile phone footage from the area, we really want to hear from you.”
Anybody with information should contact police via Live Chat at west-midlands.police.uk, quoting log 4108 of 16 December.
