Just like that, Maclin had scored more touchdowns - ONE - than all of the Kansas City Chiefs' wide receivers combined last season.
He had also showed why the Chiefs were so eager to sign him in free agency.
Without question, their pass-catching corps was among the least productive in the NFL last season, a big reason the Chiefs failed to make the playoffs. Tight end Travis Kelce led the team in receptions and yards receiving, and five of the top six in receptions were either fellow tight ends or players listed as running backs.
The only wide receiver to crack that top six? Dwayne Bowe, who was jettisoned along with his massive contract after catching just 60 balls for 754 yards - and no touchdowns.
The Chiefs signed Maclin as an upgrade, one that fits their system better. Andy Reid traded up to draft him when Reid was running the show in Philadelphia, and the two remained in touch when the coach moved on to Kansas City and Maclin was rehabbing a torn ACL two years ago.
Last year, Maclin bounced back with 85 receptions for 1,318 yards and 10 touchdowns, proving not only that he was healthy but - at least to the Chiefs - that he was a No. 1 wide receiver.
''I consider myself to be an all-around receiver, doing a little bit of everything,'' Maclin said. ''Being able to go downfield, run intermediate routes, run show routes - be able to take 1-yard passes and be able to take them to the house. I'm excited about that.''
Take them to the house? That would make the Chiefs excited, too.
To put Maclin's season a year ago into perspective, consider this: Only once has a Chiefs wide receiver ever had more catches in a season (Bowe with 86 in 2008), and Derrick Alexander and Carlos Carson are the only ones to have more yards receiving in a season.
No wonder just about everyone on the field, and the fans in the stands, where whooping it up when Maclin took that pass from Smith to the end zone on the first day of camp.
''We were just getting work in. It was part of what we installed today; me and Alex just happened to hit,'' Maclin said. ''Every day is going to be a different story. We'll continue to go out here and get work in. if it's down the field, it's down the field. If it's anything else, it's anything else. All we can do is go out there and execute the plays that are called.''
Maclin acknowledged there is some familiarity in those plays that are called. It's been a couple years since he's been in Reid's system, and there have been tweaks to it along the way. But it's not as if he's learning a foreign language, or even a different dialect.
''You know, he didn't skip a beat coming back into this,'' Smith said. ''He's really smart and sees coverages, and when you go through receivers like that, they can anticipate when the ball is coming and you kind of like that. They know the little adjustments to make.''
Maclin will be counted on for more than just production. The Chiefs still have a young and relatively unproven wide receiver corps. So despite turning 27 in May, Maclin is one of the elder statesmen.
''He understands defenses, complexity of defenses, and what they're trying to do to stop him,'' said Chiefs offensive coordinator Doug Pederson, who also worked with Maclin in Philadelphia. ''He brings a level of competitiveness that group needs and a veteran leadership within that room.''
So far, Maclin has embraced the burden that comes with his five-year, $55 million contract. He realizes that all eyes will be on him this season, especially if the Chiefs have any hopes of returning to the playoffs. He knows defenses will key on him. He is fully aware that fans expect him to not only catch passes, but score touchdowns.
One in training camp was a good start.
NOTES: S Eric Berry, back in camp after dealing with lymphoma, made a nice interception of a tipped pass in practice. Berry has been working mostly with the No. 2 defense while he gets back up to speed. ... The Chiefs have their first day off from camp on Thursday. They resume practices Friday leading up to next week's exhibition opener at Arizona.
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