ALLEN PARK, Mich. – Through his first eight weeks as an NFL offensive coordinator, Joe Lombardi has had to mix and match more than he envisioned when he took the job with the Detroit Lions this offseason.

Back then, he could look at an offense with Calvin Johnson, Reggie Bush, Joique Bell, Golden Tate and other unknown options and devise and scheme all sorts of interesting plans. Those plans, though, have been mostly hidden.

All of those players, other than Tate, have missed at least one game and it made Lombardi look at different options and lean on different players throughout the first half of the season. In doing so, he also found himself with a somewhat happy conundrum.

Running back Theo Riddick has played so well in the chances he’s been given, Lombardi now has to find a way to keep him involved in the offense, even with Bell and Bush now healthy. One way he might do that is increase the number of two-running back sets Detroit uses.

It will be specifically interesting with Bush and Riddick, who have more comparable traits. Bell is more of an inside runner.

“They both have certain skills that cross over, that are a little redundant,” Lombardi said. “In some ways they eat at each other’s reps, but they are both very good players. They are both players that can do things extremely well, and so I think you use them both. I think you get them both on the field maybe at the same time.

“Neither of them are real big guys, so you’re already saying , 'I don’t want to get this guy hit 20 times a game.' If you’ve got two of them, they can both get hit 10 times a game.”

According to ESPN Stats & Information, Bush and Riddick have not been on the field at the same time yet this season, but the Lions have run eight different two-back formations with Bush, Riddick and Bell with various receiver and tight end groupings.

In all, Detroit has run 13 plays with two running backs on the field, throwing the ball 12 times and rushing once. It has been a successful grouping for the Lions as well. Matthew Stafford has completed 10 of 12 passes for 170 yards and a touchdown with two running backs on the field and the Lions have run once for three yards.

Five of those plays have gone for first downs and the Lions are averaging 14.17 yards per pass out of it.

Detroit actually experimented with two-back formations against Atlanta than any other game, running four plays with Bell and Riddick on the field at the same time.

“Having the opportunity to kind of give [opponents] multiple sort of looks from different styles of backs and not really knowing exactly what they are going to get from them, because they all have comparable skills in some areas,” Lions coach Jim Caldwell said. “I think that will certainly add something to our offense.”

In an offense in which all of them have missed at least one game – Bush and Riddick sat two games each and Bell missed one – the depth is also a benefit along with a new wrinkle for Lombardi.

Even before Bush’s ankle sprain, Lombardi had been cognizant of overworking Bush. He kowns Bush’s history and that he had only played a full season twice in his career, so he looked for ways to potentially monitor his snaps to increase his overall health and effectiveness.

Riddick’s emergence gives Lombardi another option.

“Having another option helps us stay healthy and it just helps our team continue to move forward when a guy goes down,” Bush said. “That’s a great option to have. Like I said, the injury bug has hit our team unlike any other team I’ve been a part of, any other season I’ve been a part of.

“It’s good to know we have other options of guys who can step in and play well for us if another guy goes down.”

Or perhaps together, if they can all stay healthy at the same time.