As a matter of basic principle, it's nigh unfeasible to get successful offense off on someone who's only concern is just avoiding you altogether. Of course, if the match area were a wide open field, you could simply run them down; or, if it were in an enclosure, they would be trapped eventually. The fact that both players get reset every time they go out of bounds though, gives a categorical advantage to a man who is defending, or interested only in defending, by simply and repeatedly taking advantage of the mechanic, if he is not penalized in some way for doing so.
There are, however, still certain methods that can be more adaptive in such a context; particularly, the fact that if you know your opponents offense is little threat too you (or won't be making any appearance at all), that then in turn means you can open up to other lengths.
One example would be using more of a pinch headlock to throw by, like shown by Ken Chertow here:
The inwardness of this would be, once you dig in and get the pinch locked up, you don't necessarily need to keep going forwards, you can corral him going backwards too.
The underhook is actually a very good setup for snapdowns and works in a series with this, taking an attack depending on how up or down their posture is; getting a front headlock is also something that will let you control your opponents movement (and, you know, submit him).
Of course, if you're dealing with someone whos allergic to even getting in arms reach of you, then it can pay knowing howda sweep the leg in your back pocket.