Leverkusen have managed just one win in the past eight Bundesliga matches, leaving the club's hopes of qualifying for the UEFA Champions League in the balance.
Hyypia's charges currently sit fourth in the final Champions League spot, but fifth-placed Wolfsburg are a solitary points adrift, while Borussia Monchengladbach are just three behind.
It marks a stark contrast to the first half of the campaign when Leverkusen were challenging Borussia Dortmund for second and Hyypia has faced criticism for the downturn in form, which culminated in a disappointing 1-1 draw at home to bottom-of-the-table Eintracht Braunschweig on Saturday.
However, Leno has backed the Finn and called on the squad to improve their performances under the former Liverpool defender.
"We have let the coach down," Leno told Kicker. "We owe a lot to him. We set us up, we have implemented nothing.
"He has tried everything, and we provide a disaster such as the one against Braunschweig.
"We have to play for him now. We have let Sami down."
Leverkusen will look for a swift response to the disappointing performance against Branschweig when they visit relegation-threatened Hamburg on Friday.
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