Michael Phelps at Winter National Championships 2015: Thursday Results, Reaction

Michael Phelps was far from his Olympic best Thursday, but he was good enough. The 30-year-old finished fourth in Thursday's 200-meter medley at the 2015 AT&T Winter Nationals in Federal Way, Washington, qualifying for the final but leaving questions open about whether he can walk away with a win.

Michael Weiss won the heat with a time of 1:58.97, more than a second better than second-place Chase Kalisz. Eduardo Solaeche came in third place. Second through fifth place were decided by a smaller gap than first or second, as the 24-year-old Weiss pulled away down the stretch.

Phelps was the leader at the halfway mark but seemingly ran out of gas down the stretch. It's unclear whether he was winded or was just saving himself for his events the remainder of the weekend. Phelps is competing in the 100-meter butterfly Friday and 200-meter butterfly Saturday as he continues his preparations for the 2016 Summer Olympics in Rio de Janeiro.   

Place	Swimmer	Time
1	Michael Weiss	1:58.97
2	Chase Kalisz	2:00.09
3	Eduardo Solaeche	2:00.62
4	Michael Phelps	2:00.75
5	David Nolan	2:00.94
6	Uvis Kalnins	2:01.06
7	Patrick Mulcare	2:01.58
8	Dan Wallace	2:02.18
9	Dylan Bosch	2:02.78
10	Mack Darragh	2:02.85

This is the first time Phelps has competed at the King County Aquatics Center in 15 years.

"I think back then it was different because I was racing with so many older guys and the thing that made me so hungry was wanting to beat every single one of them," Phelps said Wednesday, per Tim Booth of the Associated Press. "Now I'm the old man. ... I think the biggest thing now is I would like to not let the young bucks beat me. And I think where I am now I'm more focused on what I should be doing at this time of year or what I want to be doing at this time of year."

The energy throughout the heat was understandably high. Not only was Phelps returning after years away from King County, but he was also doing so after formally announcing the 2016 Olympic Games would be his last, per USA Swimming. 

“Like [coach] Bob said, I’m here because this is really what I want to do, and this is how I want to finish my career,” Phelps said, per Larry Stone of the Seattle Times. “We’re going to do it my way, and we’re going to enjoy it.”

Whether Phelps' career ends with triumph or Father Time winning out is the most interesting subplot of next year. At the moment, Phelps is an 18-time gold medalist. He's already the most accomplished Olympic athlete in history regardless of how he fares in Rio. 

That said, we've increasingly seen a number of high-profile athletes hang on too long. Kobe Bryant is in the midst of a miserable final season with the Los Angeles Lakers. Peyton Manning is hobbling around Denver with nearly two times as many interceptions as touchdowns. Derek Jeter's a year removed from a disappointingly hollow farewell tour.

Phelps is younger and still competing at a higher level than all three of those men. That said, it only takes a little bit of slippage to take a swimmer from one of the best to an also-ran on the Olympic stage. A world in which fourth-place finishes are acceptable to Phelps isn't one anyone is used to.