Harare - Bitter infighting within Zimbabwe's opposition risks fatally weakening President Robert Mugabe's political foes just as the sun has begun to set on his 33-year rule.
A lasting rift within the southern African country's battle-scarred Movement for Democratic Change (MDC) now seems inevitable.
Within a few rough days, a party faction headed by long-time MDC leader Morgan Tsvangirai's erstwhile deputy Tendai Biti suspended him, and the veteran trade union leader promptly responded by expelling all involved in the move to cast him aside.
For 62-year-old Tsvangirai - who has led the party through intimidation and innumerable beatings and arrests since its founding 15 years ago - it was an unforgivable act of political fratricide.
He described the attempted party coup - which took place when both he and his deputy Thokozani Khupe were absent - as "illegal, unconstitutional, illegitimate and bogus".
The clash with Biti was a long time in the making, but the timing could hardly be worse.
Since 1999, Tsvangirai has lost three successive elections to Mugabe, whose hand rested firmly on the electoral scales each time.
The elderly leader was returned to power at the polls last year, but he is now 90.
Tsvangirai's supporters largely forgave him for the electoral defeats, but his detractors became foes when he led the MDC into a negotiated unity government with Mugabe, serving as prime minister from 2009 to 2013.
While the forced marriage helped pull Zimbabwe's crumbling economy out of free fall, prevented bloodshed and ushered in a new constitution that limits executive power, it was a political disaster for the MDC.
Mugabe, a consummate strategist, managed to reap the rewards of better government and a healthier economy while making Tsvangirai look marginal and even slightly comic.
After last year's election, Biti, the MDC's secretary general and a leading light of the party, led a group that privately pressed Tsvangirai to step down without success.
Biti and his supporters have long believed that the MDC must take a more robust approach to opposing Mugabe and his powerful Zimbabwe African National Union-Patriotic Front (Zanu-PF).
They have made the forcible removal of Tsvangirai a matter of the party's survival.
"Tsvangirai has done his best in the past 15 years as opposition leader," Jacob Mafume, spokesperson for the Biti-led faction, told AFP. "He has stayed long in power and can no longer deliver."
But Tsvangirai still "seems to enjoy grassroots support" within the rump MDC, according to political analyst Dumisani Nkomo, predicting a lasting divide in the main opposition.
"It looks like a split is inevitable in the MDC. The various factions will suspend and expel each other and at the end we will have different formations," Nkomo said.
The MDC had already split once before, with violent consequences. In 2005 former secretary general Welshman Ncube led an internal rebellion to push out Tsvangirai.
Ncube's party subsequently drained a few precious votes from the MDC, although it remains a marginal force in Zimbabwean politics.
This time the split could be far more serious, just as the MDC's goal of creating a post-Mugabe Zimbabwe lies within reach now that the president has entered his 90s.
Mugabe has ruled the former Rhodesia first as prime minister than as president since bloodshed and talks brought an end to white minority rule and independence in 1980.
While Mugabe's longevity has infuriated his political foes, a Zimbabwe without him at the helm is coming into sharper focus. A succession battle is raging within his Zanu-PF party.
As things stand, if Mugabe dies in office, or is removed, Vice President Joice Mujuru will serve out the balance of his five-year term, ruling until 2018.
Mujuru takes a less antagonistic stance than Mugabe toward foreign investors, and her stance appears to have come to the fore in the current government, while her supporters won nine of 10 provinces in recent party elections.
But she faces fierce competition from hard-line Justice Minister Emmerson Mnangagwa, who leads Zimbabwe's powerful intelligence and security forces.
If either emerges at the head of a still unified Zanu-PF they will be a formidable electoral force in 2018, particularly if the opposition vote is split further.
There could conceivably be three MDCs on the ballot papers, sharing somewhere in the region of 40 percent of the votes.
All the MDC factions will be using the time between now and 2018 elections to garner support.
The MDC faction led by Biti has hinted at forming a coalition with other opposition parties, while Tsvangirai has been instead inviting all opposition groups to join him to fight Zanu-PF.
Tsvangirai has already announced that his faction will hold an early congress this year in October.
Political infighting could yet achieve what Mugabe never fully managed - turning Zimbabwe's bold opposition into an electoral irrelevance.