ScotRail was today hit with a second remedial plan - for failing to meet passenger satisfaction targets.
The train operator has been ordered by transport secretary Michael Matheson to take rapid action to boost its score after being given a 79 per cent rating.
It is required to hit an average of 88.5 per cent in 2018-19 in the twice-yearly National Rail Passenger Survey (NRPS) by official watchdog Transport Focus.
ScotRail’s score fell by six percentage points from 85 per cent in the latest survey, carried out in the autumn and published last week.
That is the second lowest since the survey was launched 20 years ago.
The plan - to be lodged within three months - will require ScotRail “to set out how it plans to put measures in place to improve passenger satisfaction results to ensure passengers can enjoy the full benefits” of current improvement work, including two news train fleets and extra services on several lines.
It follows a separate remedial plan being ordered last month following dozens of cancellations a day on commuter lines into Edinburgh caused by the late delivery of the new trains.
Mr Matheson said: “These latest NRPS results are unsurprising and clearly linked to the recent poor performance.
“Too often, passengers have been left disappointed and this must change swiftly.
“Having already issued one remedial plan notice, it is frustrating that another follows.
“ScotRail recognises the reasons for this notice and the direct link between train service reliability and customer satisfaction.
“I require quick action to ensure the ongoing record investment in infrastructure, fleets and staff quite rightly translates to better satisfaction levels and a more attractive service.
“Passengers want and deserve a railway which delivers the benefits of more seats and services on a consistently reliable basis.”
Mr Matheson added that the performance of the ScotRail Alliance - a partnership with Network Rail - had shown a “slight improvement” over the last three months.
Scottish Greens transport spokesman John Finnie said: “ScotRail’s performance has gone from bad to worse, with delays, cancellations and overcrowding commonplace.
“The transport secretary must explain just how bad performance has to get before he will remove the contract from the abysmal operator Abellio.”
Scottish Liberal Democrat transport spokesman Mike Rumbles said: “The transport secretary is much better at issuing strongly worded letters than he is at fixing our rail service.
“The only warning ScotRail need is this - shape up and start delivering for rail passengers or we will terminate the break clause in your contract at the first opportunity.”
ScotRail head of customer operations Phil Campbell said: “We will submit a remedial plan to Transport Scotland within the timescale outlined.
“We run more than 2,400 services every weekday, which is more than ever before, and our punctuality has recently reached its highest level since September last year.
“But we know there is much more to do, given the challenges we have faced in recent months.
"Everyone is working flat out to deliver the service our customers expect and deserve.”