Wiktionary
vb. Replace something or take someone's place, especially in sports
Usage examples of "sub in".
At the moment, they were buried bow-down with most of the sub in more than three meters of silt and harder seabed with only a few meters of the stern free of the mud, the hull and frame were warped, the hold-bay doors were warped shut and unreachable, and ten of the eighteen ballast tanks had been breached.
Yet he found following the sub in the waning sunlight presented no problem.
He's brought the sub in close to confirm their desperate need for help.
David Charles stopped for a moment on the main deck to look over at his enemy outlined against the artificial lights, and saw only a black, dented hull that still looked strangely like every other sub in Norfolk.
Saturn could not have hidden a sub in Gany space without Ganymede's knowledge and acceptance.
We knew the Chinese lost such a sub in this approximate area in May 1984.
This time, they were stupid enough to bring the sub in on the surface.
Despite its requirement for stealth, the LA-class sub had one of the largest footprints of any reconnaissance sub in the water.