In a bad tempered game that saw nine players booked and Evandro shown a straight red after catching Miguel Pedro with an outstretched arm, Ricardo Horta put the hosts in front just after the half-hour mark.
Evandro was then dismissed four minutes before half-time, but fourth-placed Estoril rallied after the restart and Joao Pedro's seventh league goal of the campaign earned the visitors a share of the spoils.
There was early controversy when Bruno Miguel's header was only partially saved by Pawel Kieszek and appeared to cross the line before being clawed away, but Estoril's protests fell on deaf ears.
And the visitors' misery was compounded further when Horta slammed home Joao Mario's pull back after 33 minutes. Evandro then made contact with Pedro to receive his marching orders.
But Joao Pedro clinched a point with a close-range shot that squirmed under Kieszek.
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