So once Maclin finally put on a Chiefs jersey, it didn't take long for him to begin building a rapport with Smith. In fact, by their third preseason game Friday night, they were already demonstrating just how in synch they were.
The two hooked up seven times for 65 yards and a touchdown in less than a half.
''It was good for us,'' Maclin said. ''I felt like the first team was out there and we moved the ball every time we had the ball. One time we had a holding call down in the red zone that kind of pushed us out of there a little bit, but I thought we were pretty efficient tonight.''
Just how efficient? Smith went 15 of 20 for 146 yards and two scores, and the Chiefs led 17-0 before Tennessee finally scored. They went on to win, 34-10.
Smith has raved all training camp about how much of an upgrade Maclin is to the wide receiver corps, and the former Missouri standout tossed the praise right back at him.
''For starters, he's talented. He has what it takes to play in this league at a very high level,'' Maclin said. ''For two, he's a very intelligent person. When you combine those two things and my ability to talk to him and vice versa, it makes everything a lot easier.''
The Chiefs struggled to throw the ball last season, and a big reason why was the play of No. 1 wide receiver Dwayne Bowe. A poor fit for the Chiefs' system, he never seemed to be in concert with Smith, catching just 60 passes for 756 yards and no touchdowns.
Kansas City walked away from his massive contract - he was due $14 million against the salary cap this season - and zeroed in on Maclin, who was drafted by Chiefs coach Andy Reid when he was in Philadelphia. Once general manager John Dorsey was able to reel him in, Smith suddenly had his first downfield threat in two-plus years playing in Kansas City.
Maclin had four games last season with at least eight or more receptions, including a 12-catch, 187-yard performance at Arizona that showcased his playmaking ability. By contrast, only twice in two years did Smith and Bowe hook up at least seven times in a game.
''Jeremy has been so fluid coming in, just because of his history in the offense,'' Smith said. ''He really hasn't skipped a beat from Day 1 when he came in.''
Smith's ability to find his new top target was never more evident than on the opening drive Friday night, when the Chiefs were facing third-and-5 at the Titans 29. Smith rolled to his left and lofted a ball along the sideline for Maclin, who leaped over his defender and hauled in the pass, then tiptoed down the sideline for the game's first points.
''It was good coverage,'' Smith said. ''He's the type of guy, especially with the defender's back turned, he's so competitive with the ball in the air, he's one of those guys you feel good about letting the ball go.''
That is no small thing. Smith is conservative by nature, a quarterback who would rather take a sack or throw it away than risk an interception trying to make a big play. But with Maclin, he finally has someone with whom he is comfortable taking some risks.
''We're right where we need to be,'' Maclin said. ''The chemistry is good. I think he trusts me, I trust him. He'll put the ball in a place for me to make plays and I think that's how it's supposed to be.''
NOTES: The Chiefs selected James Winchester to serve as their long snapper, waiving Andrew East and 10 others Sunday. They still need to cut four more by Tuesday afternoon. ... Reid said he does not expect starters to play in Thursday night's preseason finale in St. Louis. ... WR De'Anthony Thomas, who's been out with a shin injury, returned to practice Sunday.
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