There is only one poor man's Welker and his name is Cole Motherfucking Beasley.
One of PFF's secret superstars of 2014.
Look at how he wins his routes.
Last year's game winning drive against the Viking's demonstrates Beasley's effectiveness and importance.
First image,
4th Q - 1:35 - 2nd & 4 - DAL 27
Beasley is in the left slot with Dez split out at the "X" on the bottom of the image. The concept of this play has all three inside receivers (Witten, Beasley, Harris) sitting in the zones at nearly the same depth. Romo will quickly hit the open receiver who has an opportunity to run after the catch for some more yards.
You can see the Vikings LBs threatening to double A-gap blitz. These LBs are also usually responsible for the shallow zones. Beasley can get to his spot before the LB(Greenway) can get back to him. You also have the safety bluffing that he will take away the short routes pre-snap. However the safety's hips betray his true intentions, they are open and the safety is bailing to make sure Bryant can't get open deep. Beasley runs his route, sits, catches the ball and runs for some extra yardage.
Second image,
4th Q - 1:30 - 2nd & 10 - DAL 45
The Vikings show a 6 man rush but only bring 5, Tony audibles for Witten to stay in protection. On the left, there is a route combination being worked by both Beasley and Dez. Beasley has burned the Vikings before on some underneath stuff, so the Vikings defenders sellout on Beasley's route and Tony's pump fake. This leaves Dez(running a 10 yard square in) to run right past the defenders with Tony hitting him in stride.
Third image,
4th Q - 1:00 - 1st & 10 - MIN 21
Flipped formation (of the previous play, personnel grouping S01), Dez and Beasley are on the other side. They run a very basic route combo, Cole runs a quick out, while Bryant runs a fade. Doesn't matter how basic the combo is because the mix of Bryant's ability to make a play over the top and Beasley's quickness underneath are perfect together. Anyway, the Vikings have an LB on Beasley playing Beasley's inside shoulder...and it is not even fair. If the defender over Beasley in the slot plays his inside shoulder, he will plant his foot and drive to the outside every time, and he will be open every time. Beasley sets up the Cowboys offense near the goal line, and the offense eventually scores the game winning TD.
There were some other plays on that drive but it doesn't matter because they didn't feature Cole Beasley.