Three of the four wide receivers who will start for the Lions on Sunday at Green Bay, were not on the 53-man roster when the season started.

Expect to see Mike Thomas, Kris Durham and Brian Robiskie see more playing time on Sunday. Lance Long was signed this week, but since he hasn’t played or practiced since the preseason it might take another week of practice to get him up to speed.

For the Lions, when one player goes down, the next is expected to step up. Just multiply that by three.

 “I expect those guys to step up, they’re here for a reason. I expect them to get open,’’ center Dominic Raiola said. “They’re not chopped liver, they can play football, they’re in the NFL, they’re here for a reason.’’

Calvin Johnson doesn’t expect to see any different coverage because he’s got three more inexperienced wide receivers playing with him.

“We’ve seen what they do in practice, we just need that stuff to translate to the field,’’ Johnson said. “We could have some very special things out of those guys.’’

  Thomas has played in five games with one start. He has three catches for 16 yards and a touchdown. (See him in photo celebrating with Calvin Johnson.)

 Robiskie was signed on Oct. 24 when Nate Burleson was placed on injured reserve. He has yet to make a catch.

 Durham was signed to the Lions practice squad on Sept. 2 after he was cut from the Seattle Seahawks camp. He’s practiced with the team since then so he knows the offense well. Plus, he played three years of college ball at Georgia with Matthew Stafford.

 “They’re all very capable. I’m very excited for their opportunity,’’ Lions offensive coordinator Scott Linehan said. “They’re all guys that are in the NFL for a reason. All of them have been drafted and been with other teams and now with ours.

“They all have unique skill sets. Mike’s got speed, and we’re going to play him some in some different positions. He’ll be able to, I think, take over some of our slot since we’ve lost our two slot receivers. Robiskie’s been a guy that’s a very good route runner, a student of the game, excellent hands. And then Durham, he’s the guy that we brought in. We had very good grades on him coming out of college and ended up going to Seattle, and then, when he was available, brought him in knowing that he was going to give us a receiver with size. We got Calvin but to be able have a receiver 6-foot-5 (Durham) on the outside that can build speed down the field I think gives us another dimension that we haven’t had on the field,’’ Linehan added. “So I think all three of them bring something pretty unique to the table.”

  Long was cut at the end of Lions training camp so he knows the offense. He had too much experience to be assigned to the practice squad.

 It should be interesting.

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