US women's football icon Megan Rapinoe limped out of the final game of her storied career Saturday, suffering a suspected torn Achilles tendon less than three minutes into the National Women's Soccer League Final which her OL Reign team lost to NJ/NY Gotham FC.

No other players were near Rapinoe when she went down on the pitch, a stunned crowd at Snapdragon Stadium holding their breath as medical staff attended her.

After several minutes, the dejected OL Reign star limped off the field, fans giving her a massive ovation as she was replaced by Bethany Balcer.

The 38-year-old American had vowed the match was "really the last one," in a career that included World Cup titles in 2015 and 2019 and gold at the 2012 London Olympics.

Despite her many achievements, Saturday's defeat means Rapinoe retires from the game without an NWSL championship title.

"It was a tough one. Definitely not how I envisioned this last one going," a tearful Rapinoe said after the game. "I am pretty sure I tore my Achilles.

"Just thank you to everyone who's been on the journey for all this time. It's been amazing, maybe besides this, I couldn't have written it any different," she added.

Celebrated for her off-field activism as well as her success on the pitch, Rapinoe announced earlier this year it would be her final season.

The 2019 FIFA Women's Player of the Year ended her epic national team career with 63 goals, earning 203 caps over more than 17 years and played her final international game in September.

Rapinoe's club career did include one title, winning the French league with Lyon in 2013 and with Reign she also won three NWSL Shields, awarded to the team with the best regular season record.

"I am just super proud of my whole career and really thankful for all that it's given me and for how long I've been able to play," she said.

"So even though it was a tough night, it was still amazing and so thankful to be here and again, so proud of our group."

Rapinoe's World Cup career also ended with bitter disappointment as she missed a penalty in the round of 16 exit defeat to Sweden in New Zealand in August - and she reflected upon those moments.

"I mean, I don't deserve this, I'll tell you that much, I am a better person than this..I thought about that a little in the last two hours. This one feels different from missing the pen in New Zealand but that's life, its' part of the game," she said.

"I know you don't always get to have the perfect ending. I've had so many perfect endings," she said citing the 2019 World Cup win amidst the successful battle with US Soccer for equal pay.

Rapinoe said she intended to remain involved in women's football, possibly in a role with the Reign.

"I'm retiring on the field but you'll definately be seeing a lot of me off the field," she said.

Gotham had taken the lead in the 24th minute with Lynn Williams slotting home after a superb run down the right and low ball from Midge Purce.

But Seattle-based Reign levelled within five minutes when Balcer sent US international Rose Lavelle through on goal and the midfielder converted with a composed finish.

Gotham then struck the woodwork twice, Purse striking the post and from the resulting scramble Delanie Sheehan hitting the bar.

Canadian Olympic gold medalist Jordyn Huitema then had a goal disallowed for offside, after being put in by a clever pass from Lavelle.

But on the stroke of half-time Gotham restored their lead when Spanish international Esther Gonzalez rose to powerfully head in a Purse corner.

There was late drama when Gotham keeper Mandy Haught was sent off for handling the ball outside the box and with all substitutes used, midfielder Nealy Martin had to go in goal for the final stages of stoppage time.

But from the resulting free-kick Lavelle was unable to test Martin, striking the wall as Gotham held on for the victory - a remarkable feat for a team which finished bottom of NWSL last season.

It was the franchise's second title, following their Women's Professional Soccer league win when the team was known as Sky Blue FC.