Hitchin Tennis Club's fourth team sealed the Datchworth summer league Division 6A title in front of a full house in a final-day thriller at Bancroft Gardens.

Jon Harris' team had already secured promotion but went into their last match of the season against Watton 3s on Monday knowing they would seal top spot if they could win a set against the only other team still in contention for the title.

Playing on Court 2 – Hitchin's equivalent of Centre Court – and roared on by an optimistic home crowd, they were made to sweat, however.

Hitchin lost a tight first set 7-6 as Sophie Adams and Stephen Pond were edged out, but Ram Sridharan brought his calm authority to court for the second set and he and Adams won 9-4 to give Hitchin the set they needed.

Watton's strong men's pair won the final set to give the visitors a 2-1 victory – and although they still have a match in hand, they trail Hitchin by four sets with only a maximum of three available. 

Hitchin 6s were also playing at home on Monday and a treated the crowd to a surprise 3-0 victory against Division 8A champions St Margaretsbury that keeps their promotion hopes alive. 

Captain Holly Hourihan and Peter Mee won the first set 10-3 before Hourihan and Matthew Ellinger took the second 9-4. Mee and Ellinger then combined to complete the clean sweep with an 8-5 win in the final set.

This is the first time Hitchin have entered a sixth team into the league and they moved up to second place in the table, a set ahead of third-placed Knebworth 7s, who still have their final game of the season to play. Because they have an inferior games-won total, Hitchin's promotion hopes will rest on St Margaretsbury beating Knebworth in straight sets next week.

St Margaretsbury's first team managed their own 3-0 win against Hitchin 3s, who still need to win a set in their final match of the season to avoid relegation from Division 3B.    

Hitchin's first team lost 2-1 to Letchworth, ending their hopes of finishing second in Division 1. Captain Claire Morrison and Paul Morris lost the opener 7-4 on a tiebreak before Morrison and Mark Rodseth won the second set 7-6. However, Morris and Rodseth were unable to claim the decider, losing 10-3.

Sarah Custance's Hitchin 5s won 2-1 away against Codicote 7s. Although they can no longer overtake leaders Codicote to win the Division 7A title, a single set from their final match of the season will be enough to guarantee promotion to Division 6. 

Hitchin 2s won 2-1 to secure their place in the third tier next season – Digswell 2s and Knebworth 2s will battle to avoid the second relegation spot in Division 3A with Elliswick 3s already down.