Matthews has not scored a 5-on-5 goal in the last seven games. Marner has been held off the scoresheet in five of the last seven games. But Toronto's top line has been inconsistent all season.
"I don't think it's the last five or seven games," stressed Keefe. "It's been up and down."
"Too many highs and lows," agreed Matthews. "Just the consistency of putting together shift after shift hasn't been there as much as we wanted."
Keefe has been pushing and prodding Matthews and Marner throughout this rollercoaster run. He even called out the top line behind closed doors following a lacklustre performance against the Detroit Red Wings in Stockholm on Nov. 17.
"It is more so just challenging Auston and Mitch to sort it out and be better," Keefe said of his previous approach.
This isn't exactly a new situation. Keefe also split up Matthews and Marner last November, which led to a strong run of form.
"Obviously not as great as it usually is and as I like it," the 26-year-old admitted. "Gotta make sure I'm staying patient out there and not trying to force anything and do what I do best. That's bring high energy, bring good pace out there, and when the puck gets into my hands trust my abilities to do things with it."
The Leafs have been outscored 15-14 with Marner, a Selke Trophy nominee last season, on the ice in 5-on-5 play. The Leafs were plus-25 in that situation last season.
"He knows he needs to be better," said Keefe. "We are going to help him through it. We have been talking with him and meeting with him. We have been working on some things on the ice that I think he has to focus on and can help him start to be the Mitch Marner that we know."
Specifically, pace of play is important.
"Just not getting the puck with a whole lot of speed with myself moving," Marner said of his biggest issue. "And not really trusting my abilities out there, so that's something that needs to change. Just have to trust it."
Marner has 20 points through 19 games, which puts him on pace for 86. He posted a career-best 99 points last season.
"He went through stretches like this last season, too, especially in the early going," Keefe reminded. "It turned out that he had an incredible season for us. I don't expect it will be any different for him