Both became examples of the fleeting nature of NFL success on Monday.
The Chiefs fired Haley less than a year removed from their division title, after a 5-8 start marked by devastating injuries and discouraging blowouts, while the Dolphins parted with Sparano amid a miserable 4-9 start that included a frustrating loss to Philadelphia on Sunday.
"The results speak for themselves," Dolphins owner Stephen Ross said at a hastily called news conference. "We're looking to becoming a winning organization, and I thought this was the best time to make the change and let us go in a direction that will allow us to become that."
The same lines were delivered in Kansas City, where friction between Haley and general manager Scott Pioli finally reached the boiling point. The Chiefs were penalized 11 times for 128 yards in a 37-10 loss to the Jets on Sunday, with Haley getting a 15-yarder for unsportsmanlike conduct.
"Timing in these situations is always difficult. There never seems to be a right time," Chiefs Chairman and CEO Clark Hunt said at a news conference. "We just felt the inconsistent play the team has experienced throughout the season, including yesterday, made today the right day to do it."
With Jacksonville having fired Jack Del Rio on Nov. 29, three franchises are now looking for a coach. Former coaches Jeff Fisher, Jon Gruden and Bill Cowher already have been connected to each of the openings, though decisions likely won't be made until the end of the season.
Until then, Todd Bowles will coach the Dolphins on an interim basis after serving as assistant head coach and secondary coach, while defensive coordinator Romeo Crennel will lead the Chiefs.
"Romeo is going to do things the way Romeo knows how," Pioli said. "I know Romeo is very similar to Todd. Todd was very passionate about football, Todd was very passionate about this football team, these players, and he was very passionate about winning. Romeo has a lot of those very qualities."
Sparano and Haley both presided over impressive turnarounds.
Sparano became the only NFL head coach to take a one-win team to the playoffs the following year, capping an 11-5 campaign in 2008 by reaching the franchise's first playoff game since 2001.
That wound up being the high-water mark for Sparano, who went 7-9 each of the past two years. Miami lost its first seven games this season before an inspired rally that started with a victory over Kansas City, but two straight losses left Sparano with a 29-32 record as the Dolphins coach.
Shortly before he was fired, Sparano held his regular Monday news conference. When asked if he wanted to comment on reports he would be fired after the season, he said no.
"I want to coach against the Buffalo Bills this week. That's my sole focus," he said.
"Everybody recognizes there's a great foundation here to build upon," Ross said. "It's not starting all over again. This isn't the way the team was when (Bill) Parcells came and they had to rebuild the entire roster."
That might be precisely the situation in which Kansas City finds itself.
The Chiefs lost starting tight end Tony Moeaki in their final preseason game, then watched as Pro Bowl safety Eric Berry and All-Pro running back Jamaal Charles went down in successive weeks. Pro Bowl quarterback Matt Cassel joined them on injured reserve when he hurt his throwing hand late in a loss to Denver on Nov. 13, the injuries unveiling a lack of depth across the roster.
After losing their first three games, the Chiefs rallied to four consecutive victories, briefly pulling into a tie atop the AFC West. But the injuries proved too difficult to overcome, and they've lost five of their last six to fall out of contention with several of the defeats coming in lopsided fashion.
Ultimately, that's what cost Haley his job.
"I guess you never expect it because you always try to be optimistic about things, but this is the NFL. It's just the nature of the beast," Chiefs linebacker Derrick Johnson said. "It goes on all the time, throughout the year. I won't say it's no big deal — it's a very big deal for the Kansas City Chiefs right now — but this goes on throughout the year."
Hunt and Pioli met late Sunday to discuss Haley's future, and again Monday morning. They met with Haley after coming to their decision and then informed the rest of the coaching staff.
Crennel met with the players shortly afterward.
"We've had one of those years where we've had injuries, and injuries to key players, but that's typical in the National Football League," Hunt said. "As a team you have to find a way to overcome that and we just weren't able to do that this year. Our play was up and down the entire season and at times it was up and down during a given game, and I think those contributed to our decision."
Pioli has said he values consistency in an organization, and that he's used the Steelers as a reference point for building the Chiefs. But his decision to part with Haley was just the second in-season firing of a head coach in franchise history — Paul Wiggins was fired after seven games during the 1977 season — and leaves the team in tumult with three games remaining.
"We went to the playoffs last year. I mean, that has to mean something," Chiefs running back Jackie Battle said. "The season didn't go the way we wanted this year, but he's proven he can win in the league. I don't know if it's fair or not, but it's part of the business."
It's a part of the business the Dolphins know all too well.
Since Don Shula retired in 1996, no coach has made it through five full seasons in Miami, and the team hasn't won a playoff game since 2000. The Dolphins are already assured of their third straight losing season, the longest such streak since the 1960s.
"Sad and disappointing news on Coach Sparano's termination," Dolphins running back Reggie Bush tweeted. "He's a great coach and an even better man! He will be greatly missed."
AP Sports Writer Steven Wine in Miami contributed to this report.