Both Getafe and Valencia have seven points after the opening games in the fourth round of the Liga season.
Two teams playing on Wednesday, including Real Madrid who welcome Valladolid, can also reach seven. Celta Vigo, who end the midweek fixtures at home to Barcelona on Thursday, can reach eight points.
Getafe had only scored once in their opening two games but struck three times in the first half against Betis, who started the day as league leaders.
Angel Rodriguez put the visitors ahead with an overhead kick after 13 minutes.
Marc Cucurella added a second in the 39th minute and two minutes later Angel added a third with a cross shot.
Betisended the match with 10 men after Aissa Mandi received a second yellow card in the 83rd minute.
In the early match, Valencia won 1-0 at Real Sociedad in a match the home team dominated.
Real Sociedad could also have gone top with a victory and dominated play but were frustrated by an impressive display from the visiting goalkeeper Jaume Domenech.
The hosts lost their fluency after changing four attacking players in a mass switch in the 67th minute.
Maxi Gomez finished off a rare Valencia counter-attack to score the winning goal from close range after 75 minutes.
“They had one chance and they won, while we did things right, playing football, but we didn’t succeed,” said Real Sociedad coach, Imanol Alguacil.
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