Brazil beat Montenegro 27-25 in Group A of the preliminary stage at the Copper Box to virtually guarantee themselves a quarter-final spot.
The South Americans, who beat Croatia 24-23 in their opening match, rattled off four successive goals to turn a 7-5 deficit into a 9-7 lead, only for Montenegro to notch four in a row themselves as they went into the break 16-15 up.
But Brazil enjoyed the better of the opening moments of the second half and a combination of quick attacking play and some powerful shooting saw them score five of the first six goals after the restart to lead 20-17.
Montenegro were operating at an unusually low conversion rate, throwing in just 55% of their efforts on goal going into the final eight minutes and Brazil took advantage, maintaining a three-goal lead with just three minutes to go.
Montenegro got one back but Brazil's victory, underpinned by Alexandra Nascimento's eight goals, takes them to four points in Group A and sets them up nicely for Wednesday's clash with Great Britain.
France pulled off a last-minute escape by scoring two goals in the final minute to draw 18-18 with Spain in Group B.
Spain looked to have set themselves up for victory very early in the game by delivering a six-goal salvo to lead 6-2 after 10 minutes and they maintained their advantage going in 10-7 up at the break.
They started strongly in the second half too and held a four-goal lead up until 13 minutes to go, but France hit back and levelled at 16-16 with 54 minutes in the clock to set up the tense finale.
They now sit just behind Republic of Korea, who beat Denmark 25-24.
The Danes, who beat Sweden 21-18 in their first game on Saturday, failed to cope with their Asian opponents' speed after the restart and their fast breaks helped open up an advantage that they just held on to.
Elsewhere, Croatia beat Angola 28-23 and Great Britain fell to Russia.
Nowrway were 24-21 winners against Sweden.