After watching a healthy Allen Robinson II shine in practice last week, Bears offensive coordinator Mark Helfrich wasn't surprised that the veteran receiver had a big game Sunday against the Lions.

In his return to action after missing two games with a groin injury, Robinson caught six passes for a season-high 133 yards and two touchdowns from quarterback Mitchell Trubisky in the Bears' 34-22 win over Detroit.

"[Robinson] had a great week," Helfrich said Monday night on the Bears Coaches Show on WBBM Newsradio 780 AM and 105.9 FM. "He and Mitch were getting more and more in sync, [developing] more and more chemistry."

Robinson wasted little time making an impact against the Lions, catching three passes for 98 yards including a 36-yard touchdown in the first quarter.

"I'm really happy with his mentality, his presence," Helfrich said. "He helped line up those other guys a few times and [he's] doing what he's here to do; make plays and lead, and he's done a fantastic job of both."

Trubisky also did a fantastic job Sunday versus Detroit, completing 23 of 30 passes for 355 yards with three touchdowns, no turnovers and a 148.6 passer rating. In the first half, the second-year quarterback posted a perfect 158.3 rating, connecting on 14 of 16 passes for 209 yards with two TDs in leading the Bears to touchdowns on each of their first four possessions of the game.

"Mitch played really, really well in the first half," Helfrich said. "He did a really good job managing a lot of different situations, getting us in and out of plays, checking protections, all those things. Four drives and four touchdowns—we'll obviously take that all day long."

Trubisky seemingly had all day to throw the majority of time he dropped back to pass—thanks to an impressive performance by the Bears offensive line.

"We had a really productive day up front in the passing game in particular," Helfrich said. "Sometimes there were some tight ends chipping in on that, sometimes some running backs as well. But we protected really well.

"On Allen Robinson's touchdown, [Trubisky] started on one side and came back. One time they kind of changed the coverage on him, and he started on one side and came back to Jordan [Howard] for an 8- or 9-yard gain. When you're able to do that and get to almost your fifth option sometimes, that just goes back to the protection."