- Lauren James was fouled by Kim Little and McCabe received a second yellow card.
- Reiten converted a penalty to seal Chelsea's victory with six minutes remaining.
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Chelsea extended their dominance at the top of the table by taking all three points in a fierce battle at Stamford Bridge.
Guro Reiten's penalty was all it took to ensure the hosts maintained their unbeaten record under new coach Sonia Bompastor, defeating their most likely title contenders in front of a record crowd for a WSL match.
Before kick-off, Chelsea announced the long-awaited arrival of world record signing Naomi Girma from the San Diego Wave.
Girma, who American coach Emma Hayes described as “the best defender I have ever seen”, joins Chelsea on a long-term contract from the NWSL, and the centre-back praised Chelsea's “winning culture” in the rest.
“This atmosphere is incredible and Chelsea has that winning culture and mentality,” he said. 'I really wanted to be part of that group with the players, the staff and what the club stands for. I think it's amazing.'
Chelsea have reportedly paid £900,000 for the 24-year-old, far surpassing the previous record paid by an English club for a player under Colombian striker Mayra Ramirez. In January last year it was believed to be €450,000 (£384,000 at the time).
Chelsea extended their dominance at the top of the table with a 1-0 win over Arsenal.
Guro Reiten's penalty was enough to ensure the hosts maintained their unbeaten record.
Before kick-off, Chelsea announced the arrival of world record signing Naomi Girma
A statement of intent in front of a WSL record crowd of 34,302, the two factors combined to create a cauldron for the visitors.
Chelsea came out flying against a nervous Arsenal defence, with Erin Cuthbert and Catarina Macario testing Arsenal goalkeeper Daphne van Domselaar in the opening minutes.
Once the great drama of the first 15 minutes had passed, Arsenal began to recover. A dodgy pass from Cuthbert almost gave Alessia Russo the opening goal, but the Gunners' number 23 tipped her England teammate Hannah Hampton's shot wide of goal.
The visitors came back a few minutes later, with Emily Fox breaking the lines and firing away.
However, they may have wished for a more natural finisher in that position, as the right back was unable to generate enough power or accuracy to squeeze the ball between Hampton's space and her far post.
Play resumed largely unchanged after the break, with Arsenal settling for more possession but unable to do much with it, and would rue the missed opportunities in the first half.
Lauren James, making her first league appearance since October, came on after a cautious first 10 minutes, before Bompastor also called on Aggie Beever-Jones and Guro Reiten as the game began to stretch into the closing stages.
Racing towards a tired Arsenal defence, James made one of her trademark runs towards the penalty area before being hauled away by Kim Little.
A furious Katie McCabe was sent off after receiving a second yellow card for dissent.
Sonia Bompastor's Chelsea are now nine points clear at the top of the WSL after Sunday's victory.
Referee Emily Heaslip pointed to the spot and a furious Katie McCabe was given her marching orders and given a second yellow card for dissent, before Reiten coolly converted.
The increasingly impatient crowd finally had something to celebrate and the late goal left Arsenal with too much to do and not enough time.
